VI.iv.5. A brother asked Abba Moses, “What is the purpose of the fasts and vigils which a man undertakes?” And the old man replied, “These are the means whereby the soul learns humility. For it is written, ‘Look upon my lowliness and labour and forgive me all my sins.’ (Psalm 25.18). If a soul does these things the Lord will have mercy on him because of them”.
VI.iv.6. A brother asked what he should do in all the temptations which came upon him, and in every thought from the devil. And the old man said to him, “With the goodness of God before his eyes he ought to weep and ask for help. He will soon find peace if he asks in total awareness, for it is written, ‘The Lord is my helper. I shall not fear what men can do to me.” (Psalm 118.6)”
Abba Moses, De Vitis Patrum Book IV, Libellus 4, Parag. 5,6