When Cain killed his brother Abel and according to Genesis 4 it is understood that God cursed Cain for his deed of killing his brother Abel. Bible does not have any reference of law being given to man by that time. How then, Cain would know what is correct and what is wrong. It is believed that marrying own sisters and brothers was not considered sin until law was given by God through Moses. Accordingly, there is no law that killing some one is a sin at the time of Cain. How should we understand this.
@valli.sujankumar There are a few lines of reasoning that might help here. It is to be expected that Cain would know murder was wrong, even if he did not have the law of Moses.
Revelation Prior to Law
People made sacrifices to God (think Abel or Noah) long before the law of God and God walked in the garden, which means that even though no law had been given the people were aware of God’s righteousness. God walked with Adam and Even in the Garden and no doubt taught them truth about Himself that was passed down to Cain and Abel. The fact that Abel offered sacrifices to God and that Cain and Abel were trying to please God actually suggest that God was still interacting with them as well.
God’s nature is evident in creation
Romans 1:20-21 - For since the creation of the world God’s invisible qualities—his eternal power and divine nature—have been clearly seen, being understood from what has been made, so that people are without excuse. For although they knew God, they neither glorified him as God nor gave thanks to him, but their thinking became futile and their foolish hearts were darkened.
God’s laws are written upon the heart of all mankind in a way that is at least perceptible
Romans 2:12-16 - All who sin apart from the law will also perish apart from the law, and all who sin under the law will be judged by the law. 13 For it is not those who hear the law who are righteous in God’s sight, but it is those who obey the law who will be declared righteous. 14 (Indeed, when Gentiles, who do not have the law, do by nature things required by the law, they are a law for themselves, even though they do not have the law. 15 They show that the requirements of the law are written on their hearts, their consciences also bearing witness, and their thoughts sometimes accusing them and at other times even defending them.) 16 This will take place on the day when God judges people’s secrets through Jesus Christ, as my gospel declares.
@SeanO Thank you for the reasoning.
God taught them the truth about Himself and while walking with God His righteousness was aware and the same was passed on to the generations until Moses gave the law. In that context how can marrying own sisters and having children is considered not sin by God while the same is considered sin after Moses law has been given. If Adam walked with God and knew about His righteousness , How could one act be considered sin from and after Moses law had been given while the same act is not considered sin before that. If it is a sin in the sight of God it shall be sin at any time. And if Cain knew that murder is against God , certainly he should have known marrying sisters is also sin if they all knew and understood about His righteousness.
@valli.sujankumar That is a good question. The general explanation is that before the law of Moses was given genetic defects were not as much of a concern, so there was no reason for it not to be allowed.
Consider the following explanation from Hugh Ross:
Hugh Ross - ”Given that we are all descended from Adam and Eve, either Cain or one of his brothers must have married a sister. This would seem to violate the commands recorded in the book of Leviticus forbidding marriage between brothers and sisters. The Levitical laws, however, must be considered in their proper historical context. Though the book of Genesis condemns sexual relations between children and their parents, it nowhere prohibits a man from marrying his sister or niece. Abraham, for example, married his half-sister without compunction. Not until the time of Moses were laws established forbidding a man from marrying a sister or niece. The timing of this command makes perfect sense biologically, for genetic defects as a result of intra-family marriage would not begin to crop up until after the first few dozen generations.”
The “law written on our hearts” is so significant. It’s like a certificate of authenticity. Genesis tells us how we are made in the image of God … we are creating “artificial intelligence” now, and the dominant opinions of science seem to express this technology as the “salvation” of humanity. But it has no heart, or sense of morals. This “law written on our hearts” is a major part of the definition of a human who was created by a loving God. Hope I didn’t spout off too much there … but it’s such a big deal to remember who we are.
13 In fact, sin was in the world before the law, but sin is not charged to a person’s account when there is no law.
14 Nevertheless, death reigned from Adam to Moses, even over those who did not sin in the likeness of Adam’s transgression.
Paul’s argument seems to be that the law did not change what was sin. Rather, the law teaches and convicts us of sin, as he says in
Romans 7:7 “I would not have known sin if it were not for the law. For example, I would not have known what it is to covet if the law had not said, Do not covet.”
So, coveting, murder, dishonoring parents and so forth did not become sin because the law was given — they were sin from the beginning. What changed, Paul indicates, is that the law made us accountable, that these offenses are now charged to our account.
@dennis.gladden Since Romans 1-2 are clear that men reject God without the law and are guilty of sin / under God’s wrath, I was curious to dive deeper into these verses. Here are some comments from the 'Zondervan Illustrated Bible Backgrounds Commentary". Very interesting stuff.
Romans 4:15 - “Where there is no law there is no transgression”
The key to the interpretation of this difficult assertion is the restricted meaning of the word ‘transgression’ (parabasis). It refers to a ‘stepping over’ of a specific law or custom. Paul’s point, then, is definitional: only when a specific law exists can sin take the specific form of a ‘transgression’. In the case of Israel, the coming of the MOsaic law brought ‘wrath’ by turning the peoples’ sin into the more serious and blameworthy category of parabasis.
Romans 5:13 - Sin is not taken into account when there is no law.
The verb ‘take into account’ (ellogeo) captures the nuance of a specific command or prohibition, since it was used to describe the careful, precise recording of accoutns necessary in book-keeping. A second-century papyrus document has two women writing to their steward: “Put down to our account everything you expend on the cultivation of the holding”
Romans 7:7 - I would not have known what sin was except through the law.
Paul seems to be claiming more than that the law simplye ‘defined’ what sin was. What he probably means is that the law gave to Israel a sense for what sin really is, in all its heinousness (Rom 7:13).
@valli.sujankumar. You have been given wonderful references for your question already, but I wanted to add. Whether you believe in evolution or GOD creation; we all come from the same genetic pool. By this reasoning, there is no way to not marry a relative.
What Leviticus law did was to establish protection against defects that would arise if we married too close to the original seeding of our immediate family. But we are all of the one human family.