And behold, one came up to him, saying, “Teacher, what good deed must I do, to have eternal life?” And he said to him, “Why do you ask me about what is good? One there is who is good. If you would enter life, keep the commandments.” (Matthew 19:16-17)
“A brother asked one of the elders: What good thing shall I do, and have life thereby?
The old man replied: God alone knows what is good. However, I have heard it said that someone inquired of Father Abbot Nisteros the great, the friend of Abbot Anthony, asking: What good work shall I do? and that he replied: Not all works are alike. For Scripture says that Abraham was hospitable and God was with him.
Elias [Elijah] loved solitary prayer, and God was with him. And David was humble, and God was with him. Therefore, whatever you see your soul to desire according to God, do that thing, and you shall keep your heart safe.” (Thomas Merton, The Wisdom of the Desert, p. 25-26)