It is impossible to draw near to God without sorrows, without which human righteousness cannot remain unchanged... If you desire virtue, than give yourself to every affliction, for afflictions produce humility. If someone abides in virtue without afflictions, the door of pride is opened to him.
Isaac of NinevehIf, at the time when the mind is praying it is distracted by any extraneous thought or worry about anything, then this prayer is not called pure.
Isaac of Nineveh