Let’s begin by reading Jeremiah 17:9, “The heart is DECEITFUL above all things, and DESPERATELY WICKED: who can know it?” Man’s heart is inherently evil, deceitful, and desperately wicked. We often think that the day in which we live is the worse that has ever been. That’s not necessarily so! Man’s heart has been sinful since the original sin of disobedience by Adam and Eve in the Garden of Eden. In fact, the first person ever born, was the first murderer. In the book of Ecclesiastes, Solomon considers the condition of things “under the sun”. In all, he uses the expression, “under the sun” 28 times in this book. He says in Ecclesiastes 1:9, “The thing that hath been, it is that which shall be; and that which is done is that which shall be done: and THERE IS NO NEW THING UNDER THE SUN.” There is no new evil in the world today. It’s all been done before! Perhaps through technology, we can sin more readily, inflict harm more vastly, and lure the innocent ones into depravity more easily…but it’s all been done before!

I wanted to point that out before considering your question because Leviticus, chapter 20, warns against some of the gravest, most degrading, and outrageous sins. These things were in the hearts of men a long, long time ago. All of the sins listed in chapter 20 are given in chapters 18-19 as being wrong. In chapter 20, the Lord pronounces strict and swift judgment for sins such as:

  • OFFERING THEIR CHILDREN TO A FALSE GOD (verses 1-5) –Punishment: STONED TO DEATH.
  • GOING TO WIZARDS, SOOTHSAYERS, AND PSYCHICS (verses 6-8). Punishment: CUT OFF FROM THE PEOPLE. This could indicate death, or possibly excommunication.
  • CHILDREN CURSING, OR DISRESPECTING THEIR PARENTS (verse 9). Punishment: DEATH.
  • COMMITTING ADULTERY (verse 10). Punishment: DEATH.
  • ENGAGING IN INCEST (verses 11-12). Punishment: DEATH.
  • ENGAGING IN SODOMY, A HOMOSEXUAL ACT (verses 13). Punishment: DEATH.
  • MARRYING A WOMAN AND HER MOTHER (verse 14). Punishment: BURN WITH FIRE. This could mean being burnt to death, being put to death and then having the bodies burnt, or it could indicate being burnt with a hot brand to distinguish their terrible sin among the people.
  • BESTIALITY (verses 15-16). Punishment: DEATH FOR THE PERSON AND THE BEAST.
  • DIFFERENT KINDS OF INCEST AND UNCLEANNESS (verses 17-21).
    • INCEST WITH A SISTER OR HALF-SISTER. Punishment: THEY SHALL BE CUT OFF FROM THE PEOPLE. HE SHALL BEAR HIS INIQUITY, possibly death, or marked for shame.
    • SEX WITH A WOMAN ON HER PERIOD. Punishment: BOTH SHALL BE CUT OFF FROM THE PEOPLE.
    • INCEST WITH AN AUNT. Punishment: THEY SHALL BEAR THEIR INIQUITY.
    • INCEST WITH AN UNCLE’S WIFE. Punishment: THEY SHALL BEAR THEIR INIQUITY AND DIE CHILDLESS. (The uncle’s wife would have married into the family.)
    • SEX WITH YOUR BROTHER’S WIFE. Punishment: THEY SHALL BE CHILDLESS.

Although the Lord forbids and condemns each of these sins, only incest and bestiality is still punishable by law…and that may be changing soon!   As to your question in verse 21, concerning a man sleeping with his brother’s wife, this would refer to having an affair with your brother’s wife, or living with your brother’s wife while he is still living. This was the sin that Herod committed and was confronted by John the Baptist. We read in Mark 6:18, “For John had said unto Herod, It is not lawful for thee to have thy brother’s wife.” Although most of these sins are accepted or even celebrated today, the Lord said in Malachi 3:6, “I change not.” He has not changed His mind about the wrongness of these sins. (240.2)