The Sin Unto Death -- Voddie Baucham

15 And if we know that he hears us in whatever we ask, we know that we have the requests that we have asked of him.

16 If anyone sees his brother committing a sin not leading to death, he shall ask, and God will give him life—to those who commit sins that do not lead to death. There is sin that leads to death; lI do not say that one should pray for that. 17 All wrongdoing is sin, but there is sin that does not lead to death.