Thanks for your question, Sin is the breaking of the commandments of God.
We all sin.
Ezekiel 18:4 Behold, all souls are mine; as the soul of the father, so also the soul of the son is mine: the soul that sinneth, it shall die.
We all die.
Romans 3:23 For all have sinned, and come short of the glory of God;
Romans 5:12 Wherefore, as by one man sin entered into the world, and death by sin; and so death passed upon all men, for that all have sinned:
The commandments of God were encapsulated in the 10 commandments given to Moses.
An attempt to keep the Law of Moses will end in failure at some point.
James 2:10 For whosoever shall keep the whole law, and yet offend in one point, he is guilty of all.
The result is that we are all guilty before God and the Law shows us so to be.
Romans 3:19 Now we know that what things soever the law saith, it saith to them who are under the law: that every mouth may be stopped, and all the world may become guilty before God.
No one can be justified in the sight of God by attempting to keep the Law.
Romans 3:20 Therefore by the deeds of the law there shall no flesh be justified in his sight: for by the law is the knowledge of sin.
Which brings us to Christ who kept and fulfilled the Law in all points.
Romans 10:4 For Christ is the end of the law for righteousness to every one that believeth.
Belief, repentance and Baptism into Christ washes away all our sins to that point.
Acts 22:16 And now why tarriest thou? arise, and be baptized, and wash away thy sins, calling on the name of the Lord.
By submission to baptism our sins are covered and guilt for them disappears.
In this way Baptism is the answer of a good conscience.
1 Peter 3:21 The like figure whereunto even baptism doth also now save us (not the putting away of the filth of the flesh, but the answer of a good conscience toward God,) by the resurrection of Jesus Christ:
After baptism we endeavour to live with a new set of principles, weighing our actions against the commandments of Christ – the law of love written in our hearts.
Romans 2:15 Which shew the work of the law written in their hearts, their conscience also bearing witness, and their thoughts the mean while accusing or else excusing one another;)
We will still sin but John gives us the remedy:
1 John 1:7 But if we walk in the light, as he is in the light, we have fellowship one with another, and the blood of Jesus Christ his Son cleanseth us from all sin.
8 If we say that we have no sin, we deceive ourselves, and the truth is not in us.
9 If we confess our sins, he is faithful and just to forgive us our sins, and to cleanse us from all unrighteousness.
10 If we say that we have not sinned, we make him a liar, and his word is not in us.
1 John 2:1 My little children, these things write I unto you, that ye sin not. And if any man sin, we have an advocate with the Father, Jesus Christ the righteous:
2 And he is the propitiation for our sins: and not for ours only, but also for the sins of the whole world.
From this we understand that if we are truly trying to live our lives in Christ we are assured of forgiveness on request for those sins we cannot help. If our forgiveness is assured and the sin put behind us there should be no guilt as a matter of faith.
It is the way we deal with others that is important.
1 Corinthians 11:27 Wherefore whosoever shall eat this bread, and drink this cup of the Lord, unworthily, shall be guilty of the body and blood of the Lord.
Eating and drinking unworthily is not primarily about sin (Christ died to free us from sin); it is about whether we are giving ourselves for others in the way Christ gave himself for us.
God’s love is demonstrated to us in his willingness to forgive our sins at the cost of giving his only begotten son. Christ’s love was demonstrated in the sacrifice of his life for us.
He will judge us not on our ability to be sinless but on the love we have shown to our fellow man.
Matthew 25:40 And the King shall answer and say unto them, Verily I say unto you, Inasmuch as ye have done it unto one of the least of these my brethren, ye have done it unto me.
Matthew 25:45 Then shall he answer them, saying, Verily I say unto you, Inasmuch as ye did it not to one of the least of these, ye did it not to me.
In conclusion, sin and guilt separates us from God as part of our Adamic nature but when we put on Christ by baptism we begin a new life free from the consequences of sin and death. We are brought near to God and our sins are remembered no more.
Hebrews 10:16 This is the covenant that I will make with them after those days, saith the Lord, I will put my laws into their hearts, and in their minds will I write them;
17 And their sins and iniquities will I remember no more.
18 Now where remission of these is, there is no more offering for sin.
19 Having therefore, brethren, boldness to enter into the holiest by the blood of Jesus,
20 By a new and living way, which he hath consecrated for us, through the veil, that is to say, his flesh;
21 And having an high priest over the house of God;
22 Let us draw near with a true heart in full assurance of faith, having our hearts sprinkled from an evil conscience, and our bodies washed with pure water.
23 Let us hold fast the profession of our faith without wavering; (for he is faithful that promised;)
24 And let us consider one another to provoke unto love and to good works:
25 Not forsaking the assembling of ourselves together, as the manner of some is; but exhorting one another: and so much the more, as ye see the day approaching.
I hope this helps.
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