1 John 5:14-17

And this is the confidence that we have in him, that, if we ask any thing according to his will, he heareth us: and if we know that he hear us, whatsoever we ask, we know that we have the petitions that we desired of him. If any man see his brother sin a sin which is not unto death, he shall ask, and he shall give him life for them that sin not unto death. There is a sin unto death: I do not say that he shall pray for it. All unrighteousness is sin: and there is a sin not unto death.
1 John 5:14-17