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14And this is the confidence which we have in him, that if we ask anything according to his will he hears us. 15And if we know that he hears us in whatever we ask, we know that we have obtained the requests made of him. 16If any one sees his brother committing what is not a mortal sin, he will ask, and God will give him life for those whose sin is not mortal. There is sin which is mortal; I do not say that one is to pray for that. 17All wrongdoing is sin, but there is sin which is not mortal.
1 John 5:14-17 (RSV)