Understanding the law of God brings us to understand that we have sinned against Him, for:
Romans 3:23  For all have sinned, and come short of the glory of God; 

If not of the law, we would not know what sin is.
Romans  7:7    What shall we say then? [is] the law sin? God forbid. Nay, I had not known sin, but by the law: for I had not known lust, except the law had said, Thou shalt not covet. 

Understanding the law brings us to understand that we should be the one worthy of death but Jesus came to die for us and redeemed us from the curse of the law for we know that
Romans 6:23 for the wages of sin is death

Understanding the law brings us to understand that we need a Saviour to help us keep the law.
Romans 5:8     But God commendeth his love toward us, in that, while we were yet sinners, Christ died for us. 

Understanding of the law brings us to understand that death is the payment for sin.
Romans 6:23 For the wages of sin [is] death; but the gift of God [is] eternal life through Jesus Christ our Lord. 

So, now that we know that we have come short and have sinned, what do we need to do when we are convicted of sin? The answer is confess and be forgiven and repent.

What is confession and forgiveness?
Let’s see the ensamples of the old covenant
Leviticus 5:5   And it shall be, when he shall be guilty in one of these [things], that he shall confess that he hath sinned in that [thing]:   5:6      And he shall bring his trespass offering unto the LORD for his sin which he hath sinned, a female from the flock, a lamb or a kid of the goats, for a sin offering; and the priest shall make an atonement for him concerning his sin. 

Step 1: The sinner is guilty
Step 2: Bring a trespass offering (lamb, turtledove, etc)
Step 3: Confess his sin to the trespass offering


Step 4: Forgiveness: The priest shall make an atonement for him concerning his sin

What is meaning of confess in its original term?
H3034 yadah – yaw-daw
To use the hand, to throw at or away, to shoot, bemoan (sorrowful or discontent over something)

So, we see here the purpose of the confession on the part of the guilty for breaking the law of God. Picture yourself holding a piece of stone. If the stone represents your sin, confession means now you have throw that stone away. Shoot it somewhere and feel sorrowful about it.

Also, we need to remember that when we confess, it needs to be the particular sin. WE need to acknowledge specific sins.

What about in the new covenant?
The same principles apply except for the ceremonial duties that were nailed to the cross.

Colossians 2:13 And you, being dead in your sins and the uncircumcision of your flesh, hath he quickened together with him, having forgiven you all trespasses;  2:14 Blotting out the handwriting of ordinances that was against us, which was contrary to us, and took it out of the way, nailing it to his cross; 

He – Jesus Christ
Forgiven you all trespasses – how?
John 1:29 The next day John seeth Jesus coming unto him, and saith, Behold the Lamb of God, which taketh away the sin of the world.

Romans 3:25   Whom God hath set forth [to be] a propitiation through faith in his blood, to declare his righteousness for the remission of sins that are past, through the forbearance of God; 

1 John 2:2 And he is the propitiation for our sins: and not for ours only, but also for [the sins of] the whole world.  4:10Herein is love, not that we loved God, but that he loved us, and sent his Son [to be] the propitiation for our sins. 

Jesus was the Lamb crucified for the forgiveness of our sins. Since He came as the fulfillment of the shadow in the ceremonial laws, these ordinances were blotted at the cross. The new covenant is no more contrary to us because Jesus made the way easier into the Most Holy Place, a simple way and access to the Father in heaven for the forgiveness of sins. All we have to do is to have faith in Him as the One who died for us and has redeemed us from the curse of the law.

Galatians 3:13 Christ hath redeemed us from the curse of the law, being made a curse for us: for it is written, Cursed [is] every one that hangeth on a tree: 

Why is the handwriting of ordinances contrary to us or against us?

1. Depletes your resources
Every time you commit sin, you have to take your resources either lamb, turtledove or a measure of flour if you are very poor. What happens if you sin more often? How many lamb will one consume at a given time?

2. Others will see that you have sinned
Every eye can see you taking your sacrificial offering, therefore, putting you to open shame before the eyes of many. This will encourage backbiting and gossiping and evil thinking too.

3. Loss of your loved animals
Imagine you have to kill your own animal whom you have cared for a certain time.

4. You have to build a literal altar of sacrifice
It means you need to construct a literal altar if you are far from the literal sanctuary. Every household that is far from the sanctuary must have a literal altar of sacrifice

5. You have to spend time and effort to go to the sanctuary or to your altar in order to offer your sacrifice
It means you have to leave whatever you are doing in order to walk and take your sacrifice into the tabernacle.

6. Routinary and can become a formality
One can think he can just get away with his sin anytime as long as he does the required sacrifice.

 7. The priest will die if someone in the camp has an unconfessed sin
Today, if you have unconfessed sin, you will be accountable of it and not your minister. If the ordinance is still to be followed today, it would mean that your beloved pastor or minister will die in the day of atonement if one of his church members has unconfessed sin/s.

In the new covenant, the process remains the same:
Step 1: The sinner is guilty

Who convicts us that we are guilty of a particular sin?
John 16:7 Nevertheless I tell you the truth; It is expedient for you that I go away: for if I go not away, the Comforter will not come unto you; but if I depart, I will send him unto you.  16:8  And when he is come, he will reprove the world of sin, and of righteousness, and of judgment: 

It is the 3rd person of the Godhead family that specifically convicts us of sin. It is very important to understand the 3rd Person and accept Him into our lives so that when we sin we can immediately realize that we have done wrong against our neighbors or against God.

There are people who are self righteous and they do not realize their sins. Instead they say I did not sin.
What are they called?
1 John 1:10       If we say that we have not sinned, we make him a liar, and his word is not in us. 
Therefore, the first step to repentance is realizing your are guilty of breaking the law of God. The first step is important for if there is no first step there is no second step. If you do not realize you are guilty, then you will not realize that you need to confess and change your life.

Sometimes God allows others way that you are convicted of sin,

He allows sickness to happen your life

Example:
Miriam and Aaron spoke against Moses and God was angry at Miriam and set leprosy to her. Now they realized they have sinned against their brother Moses and against God. They were only convicted of sin after they saw the leprosy. The story is found in Numbers chapter 12

He sends messengers to rebuke you, example, Nathan to David
When David coveted after Bathseba and committed adultery God sent Nathan the prophet to rebuke David and David was convicted of his sin. The story is found in 2 Samuel chapter 12

God sends vision and dreams
God sends dreams and visions to His prophets regarding particular sins of certain people that God wants to be dealt with

Step 2: Bring a trespass offering – Go to the Father, Take the name of Jesus who died for us
1 Timothy 2:5 For [there is] one God, and one mediator between God and men, the man Christ Jesus;   2:6 Who gave himself a ransom for all, to be testified in due time. 

1 John 1:9-10, “If we confess our sins, he is faithful and just to forgive us [our] sins, and to cleanse us from all unrighteousness.  If we say that we have not sinned, we make him a liar, and his word is not in us.” 

It is only through the blood of the Lamb that our sins are forgiven. Jesus Christ makes atonement in our behalf for He had shed His blood. We did not shed our blood for He did it for us. This is forgiveness.

Step 3: Confess his sin to the trespass offering – Confess your sins to Christ
Do not confess your sins to a sinful human being but only to Christ:
Psalms 32:5 “I acknowledged my sin unto thee, and mine iniquity have I not hid. I said, I will confess my transgressions unto the LORD; and thou forgavest the iniquity of my sin.

Matthew 9:6 “But that ye may know that the Son of man hath power on earth to forgive sins, (then saith he to the sick of the palsy,) Arise, take up thy bed, and go unto thine house.”

Thee – refers to Christ the Lord who forgives our sins
No human ears should know any particular sin that you have committed. It will encourage gossiping and backbiting.

In the catholic church, they confess their sins to the priest. Why?

But this is blasphemy
Mark 2:7 Why doth this [man] thus speak blasphemies? who can forgive sins but God only? 

Also, confess your fault to the one you have offended and to no other else

James 5:16“Confess [your] faults one to another, and pray one for another, that ye may be healed. The effectual fervent prayer of a righteous man availeth much.”

How many times do you have to forgive others of the fault they have committed against you?
Matthew 18:21 Then came Peter to him, and said, Lord, how oft shall my brother sin against me, and I forgive him? till seven times?  18:22 Jesus saith unto him, I say not unto thee, Until seven times: but, Until seventy times seven. 

Luke 17:3-4, "Take heed to yourselves: If thy brother trespass against thee, rebuke him; and if he repent, forgive him. And if he trespass against thee seven times in a day, and seven times in a day turn again to thee, saying, I repent; thou shalt forgive him." 

Also, after you forgive someone, move on and stop recalling for it is not the will of God. Plus, it will add stress to your life, shortens your life, affects others in a negative way, does not profit you anything good. It’s a waste of time to keep recalling the sins of others. What if it’s being done unto you? Do you want others to recall your sins?

What happens if you do not forgive others
Matthew 6:14 For if ye forgive men their trespasses, your heavenly Father will also forgive you:  6:1 But if ye forgive not men their trespasses, neither will your Father forgive your trespasses. 

It means that if we do not know how to forgive others, our sins will remain in the record books unpardoned and these sins will stand against us in the day of judgment and we will surely be found wanting.

Step 4: Forgiveness: The priest shall make an atonement for him concerning his sin – Jesus Christ our High Priest shall make atonement for our sins.

What did God promise when we confess our sins?
Jeremiah 31:33-34, “But this [shall be] the covenant that I will make with the house of Israel; After those days, saith the LORD, I will put my law in their inward parts, and write it in their hearts; and will be their God, and they shall be my people.  And they shall teach no more every man his neighbour, and every man his brother, saying, Know the LORD: for they shall all know me, from the least of them unto the greatest of them, saith the LORD: for I will forgive their iniquity, and I will remember their sin no more.”

1 John 1:9 If we confess our sins, he is faithful and just to forgive us [our] sins, and to cleanse us from all unrighteousness. 

Acts 3:19, Repent ye therefore, and be converted, that your sins may be blotted out, when the times of refreshing shall come from the presence of the Lord.”

Jeremiah 31:34 …for I will forgive their iniquity, and I will remember their sin no more.”

Psalms 103:12 As far as the east is from the west, [so] far hath he removed our transgressions from us. 

Isaiah 1:18 Come now, and let us reason together, saith the LORD: though your sins be as scarlet, they shall be as white as snow; though they be red like crimson, they shall be as wool. 

Psalms 32:1 Blessed [is he whose] transgression [is] forgiven, [whose] sin [is] covered. 

Apart from sins being wiped out, we will also be blessed.

What is repentance?
 H7725  shub – shoob
To turn back, retreat, back, away, withdraw, return

“Therefore say unto the house of Israel, Thus saith the Lord GOD; Repent, and turn yourselves from your idols; and turn away your faces from all your abominations.”— Ezekiel 14:6 (KJV)

“Therefore I will judge you, O house of Israel, every one according to his ways, saith the Lord GOD. Repent, and turn yourselves from all your transgressions; so iniquity shall not be your ruin.  — Ezekiel 18:30 (KJV)

“But if the wicked will turn from all his sins that he hath committed, and keep all my statutes, and do that which is lawful and right, he shall surely live, he shall not die.”   — Ezekiel 18:21 (KJV)

“Wash you, make you clean; put away the evil of your doings from before mine eyes; cease to do evil;”   — Isaiah 1:16 (KJV)

G3340 metanoeo – metano-eh-o
To think differently or afterwards reconsider

“And be not conformed to this world: but be ye transformed by the renewing of your mind, that ye may prove what is that good, and acceptable, and perfect, will of God.”   — Romans 12:2 (KJV)

“Afterward Jesus findeth him in the temple, and said unto him, Behold, thou art made whole: sin no more, lest a worse thing come unto thee.”   — John 5:14 (KJV)

“She said, No man, Lord. And Jesus said unto her, Neither do I condemn thee: go, and sin no more.”   — John 8:11 (KJV)

 Example;

Luke 23 (KJV)
¯¯¯¯¯¯¯¯¯¯
⁴⁰ But the other answering rebuked him, saying, Dost not thou fear God, seeing thou art in the same condemnation?
⁴¹ And we indeed justly; for we receive the due reward of our deeds: but this man hath done nothing amiss.
⁴² And he said unto Jesus, Lord, remember me when thou comest into thy kingdom.

“And the times of this ignorance God winked at; but now commandeth all men every where to repent:”   — Acts 17:30 (KJV)

Does God hold you accountable for a sin that you have no knowledge about?
Acts 17:30, “And the times of this ignorance God winked at; but now commandeth all men every where to repent.”

Example:

What else is symbolized by repentance and forgiveness?
The laver in the outer court

When we confess our sins Jesus cleanse us like the water can remove the dirt and dust from our body. Jesus the living water can cleanse us. Confession is like wanting to be cleanse from the dirt of sin in our lives.

James 4:8, “Draw nigh to God, and he will draw nigh to you. Cleanse [your] hands, [ye] sinners; and purify [your] hearts, [ye] double minded.” 

Psalms 51:7     Purge me with hyssop, and I shall be clean: wash me, and I shall be whiter than snow. 

Isaiah 1:16       Wash you, make you clean; put away the evil of your doings from before mine eyes; cease to do evil

It means if we confess and repent we are being washed from the dirt of sin. Why do we need to be washed? Because nothing that defiles can enter heaven.

Revelation 21:27 And there shall in no wise enter into it any thing that defileth, neither [whatsoever] worketh abomination, or [maketh] a lie: but they which are written in the Lamb's book of life.

What happens if you do not repent?
Luke 13:3 “I tell you, Nay: but, except ye repent, ye shall all likewise perish.”

2 Peter 3:9 “The Lord is not slack concerning his promise, as some men count slackness; but is longsuffering to us-ward, not willing that any should perish, but that all should come to repentance.”

Revelation 2:5, “Remember therefore from whence thou art fallen, and repent, and do the first works; or else I will come unto thee quickly, and will remove thy candlestick out of his place, except thou repent.”

So repentance is turning away from sin! What are we to do when we know that we have sinned other than to stop doing it?

Acts 2:38, “Then Peter said unto them, Repent, and be baptized every one of you in the name of Jesus Christ for the remission of sins, and ye shall receive the gift of the Holy Ghost.”

John 5:14, “Afterward Jesus findeth him in the temple, and said unto him, Behold, thou art made whole: sin no more, lest a worse thing come unto thee.“

Matthew 6:23 But if thine eye be evil, thy whole body shall be full of darkness. If therefore the light that is in thee be darkness, how great [is] that darkness! 

Matthew 12:43 When the unclean spirit is gone out of a man, he walketh through dry places, seeking rest, and findeth none.  12:44  Then he saith, I will return into my house from whence I came out; and when he is come, he findeth [it] empty, swept, and garnished.   12:45  Then goeth he, and taketh with himself seven other spirits more wicked than himself, and they enter in and dwell there: and the last [state] of that man is worse than the first. Even so shall it be also unto this wicked generation. 

Hebrews 6:4    For [it is] impossible for those who were once enlightened, and have tasted of the heavenly gift, and were made partakers of the Holy Ghost,  6:5 And have tasted the good word of God, and the powers of the world to come,   6:6 If they shall fall away, to renew them again unto repentance; seeing they crucify to themselves the Son of God afresh, and put [him] to an open shame. 

Hebrews 10:26 For if we sin wilfully after that we have received the knowledge of the truth, there remaineth no more sacrifice for sins, 10:27   But a certain fearful looking for of judgment and fiery indignation, which shall devour the adversaries.