King David committed murder, and God put away his sin so that he did not face death under the law. Likewise for Christians.
Did you understand what you just wrote? He sinned, he broke the Law, it was the sin that was put away, not the Law.
But David did suffer consequences for his wrongs.
Likewise God chastises Christians should they do wrong.
If there is no Law or the Law does not apply to them, they can do no wrong...
Rom 5:13 (For until the law sin was in the world: but sin is not imputed when there is no law.
Yet, we are told this...
1Jn 1:8 If we say that we have no sin, we deceive ourselves, and the truth is not in us.
1Jn 1:9 If we confess our sins, he is faithful and just to forgive us our sins, and to cleanse us from all unrighteousness.
1Jn 1:10 If we say that we have not sinned, we make him a liar, and his word is not in us.
and then read on...
1Jn 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:
1Jn 2:2 And he is the propitiation for our sins: and not for ours only, but also for the sins of the whole world.
Christ is the propitiation for our sins. We still sin, we still break the Law, but Christ paid the penalty, we are no longer under the DEATH PENALTY, no longer under the Law.
Rom 6:23 For the wages of sin is death; but the gift of God is eternal life through Jesus Christ our Lord.
Who is the brother this scripture refers to?
Matt 12:50
For whoever does the will of My Father in heaven (believe on Jesus, John 6:40) is My brother and sister and mother.
A Christian's life is hid with Christ in God, Col 3:3. When we believe on Jesus, following him, we walk in the Spirit. He is our brother.
But if we walk in the flesh (unbelief, such as turning back to righteousness by works of the law), then such have spiritually murdered their brother, Jesus. Such have rejected God's will that we believe on Jesus, Matt 12:50, John 6:40. Such are like Cain, who murdered his brother Able.
1John 3:12
not as Cain who was of the wicked one and murdered his brother
Rejecting Christ is not the same as committing a sin and the repenting...
We have already read I John 1:8 - 2:2 which is the case for committing sin and repenting, then there is the deliberate choice of rejecting God's way and turning to sin with no remorse...
Heb 10:26 For if we sin wilfully after that we have received the knowledge of the truth, there remaineth no more sacrifice for sins,
Heb 10:27 But a certain fearful looking for of judgment and fiery indignation, which shall devour the adversaries.