St. Ignatius (Brianchaninov). "On Prelest". On Guarding Oneself from the Good That Belongs to Fallen Human Nature.
Has some good thought come to you? Stop: whatever you do, do not rush to implement it or carry it out overhastily, without thinking. Have you felt some good impulse or inclination in your heart? Stop; do not dare to be drawn by it. Check it with the Gospel. See whether your good thought and your heart's good impulse tally with the Lord's holy teaching. You will soon see that there is no agreement whatever between the good of the Gospel and the good of fallen human nature.
The good of our fallen nature is mixed with evil, and therefore this good has itself became evil, just as delicious and wholesome food becomes poison when it is mixed with poison. Guard yourself from doing the good of fallen nature. By doing this good, you develop your own fall, you develop within you self-opinion and pride, and you will attain the closest conformity with demons. On the other hand, by doing the good of the Gospel as a true and faithful disciple of the God-Man, you will become like the God-Man. “He that loveth his life shall lose it; and he that hateth his life in this world shall keep it unto life eternal” (Joh. 12:25).
“Whosoever will come after me, let him deny himself, and take up his cross, and follow me. For whosoever will save his life shall lose it; but whosoever shall lose his life for my sake and the gospel's, the same shall save it.” (Mk 8:34-35)
The Lord orders the complete renunciation of fallen nature, and hatred for its motives and impulses, not only for those which are clearly evil, bur for all without exception, even the apparently good. It is a great disaster to follow the righteousness of fallen nature. This implies and involves rejection of the Gospel, rejection of the Redeemer, rejection of salvation. “If any man come to me, and hate not…. yea, and his own life also, he cannot be my disciple” (Luk.24:26), said the Lord.