What is a sin that leads to death?

¹⁶ If you see any brother or sister commit a sin that does not lead to death, you should pray and God will give them life. I refer to those whose sin does not lead to death. There is a sin that leads to death. I am not saying that you should pray about that. ¹⁷ All wrongdoing is sin, and there is sin that does not lead to death. (1 John 5:16-17)

Sins that lead to death are things such as murder (Numbers 35:30), adultery (Deuteronomy 22:22), fornication with someone engaged (Deuteronomy 22:23-24), rape (Deuteronomy 22:25-27), kidnapping and sex trafficking (Deuteronomy 24:7), sorcery (Deuteronomy 22:28), openly serving another God (Deuteronomy 13:6-9), bestiality (Exodus 22:19), abortion (Leviticus 20:2), cursing God’s name (Leviticus 24:16), persistent rebellion towards parents (Deuteronomy 21:18-21), and incest (Leviticus 20:12). All the sins listed are punishable by death; therefore, they are sins that lead to death. Any believer who wants to walk in fellowship with the body must judge correctly and not allow these types of behaviors in a fellow believer. If the crime is punishable by law, be thankful there is a minister of God, an avenger who brings wrath on the one who practices evil (Romans 13:4). And if not,

¹⁰ “Cursed be the one who does the LORD’S work negligently,
And cursed be the one who restrains his sword from blood. (Jeremiah 48:10)

And,

¹² For the word of God is living and active and sharper than any two-edged sword, and piercing as far as the division of soul and spirit, of both joints and marrow, and able to judge the thoughts and intentions of the heart. (Hebrews 4:12)

References

1 John 5:16-17

Numbers 35:30

Deuteronomy 22:22-28

Deuteronomy 24:7

Deuteronomy 13:6-9

Exodus 22:19

Leviticus 20:2

Leviticus 24:16

Deuteronomy 21:18-21

Leviticus 20:12

Romans 13:4

Jeremiah 48:10

Hebrews 4:12