Selected quotes from St. Maximos the Confessor

"Thoughts are directed to things. Now, of things some are sense perceptible, some mental. The mind, then, tarrying with these things, carries about with itself thoughts of them; but the grace of prayer joins the mind to God, and joining to God withdraws it from every thought. Then the mind, associating only with Him, becomes God-like. And being such, it asks of Him what is proper and at no time fails of its petition. Therefore the Apostle commands to 'pray without ceasing.' that, unremittingly joining our mind to God, we may little by little break off our passionate clinging to material things."

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"Divine Scripture commands nothing impossible, since the Apostle himself both sang psalms and read and ministered and prayed without ceasing. For unceasing prayer is to keep the mind in great reverence and attached to God by desire, and to cling always to hope in Him, to be of good courage in Him in all things, alike in our activity and in what befalls us. It was in such a disposition that the Apostle said: 'Who shall separate us from the love of Christ?"

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"The whole purpose of the Savior's commandments is to free the mind from incontinence and hate and to bring it to the love of Himself, and of its neighbor. From these is begotten the splendor of holy knowledge, actually possessed."