Someone who bears a grudge while he prays is like a person who sows in the sea and expects to reap a harvest.
Isaac of NinevehIf you practice an excellent virtue without perceiving the taste of its aid, do not marvel; for until a man becomes humble, he will not receive a reward for his labor. Recompense is given, not for labor, but for humility.
Isaac of NinevehNo one can sense his own weakness is at least a small temptation is not allowed to afflict either his body or his soul. Then, comparing his weakness to the help of God, a man comes to know its magnitude. But whoever does not know that he needs God's help, let him make many prayers. Insofar as he multiplies them, in that measure will he be humbled.
Isaac of NinevehBe persecuted, rather than be a persecutor. Be crucified, rather than be a crucifier. Be treated unjustly, rather than treat anyone unjustly. Be oppressed, rather than be an oppressor. Be gentle rather than zealous. Lay hold of goodness, rather than justice.
Isaac of NinevehLove sinners, but hate their deeds, and do not disdain sinners for their failings, so that you yourself do not fall into the temptation in which they abide... Do not be angry at anyone and do not hate anyone, neither for their faith, nor for their shameful deeds... Do not foster hatred for the sinner, for we are all guilty... Hate his sins, and pray for him, so that you may be made like unto Christ, who had no dislike for sinners, but prayed for them.
Isaac of Nineveh