The whole purpose of the Savior’s commandments

Maximos the Confessor (c. 580 – 662), from the Philokalia:

The whole purpose of the Savior’s commandments is to free the intellect from dissipation and hatred, and to lead it to the love of Him and one’s neighbor. From this love springs the light of active holy knowledge.

– Four Hundred Texts on Love, Fourth Century

Along the same lines:

He who always concentrates on the inner life becomes restrained, long-suffering, kind and humble. He will also be able to contemplate, theologize and pray. That is what St Paul meant when he said: ‘Walk in the Spirit’ (Gal. 5:16).

One ignorant of the spiritual path is not on his guard against impassioned conceptual images, but devotes himself entirely to the flesh. He is either a glutton, or licentious, or full of resentment, anger and rancor. As a result he darkens his intellect, or he practices excessive asceticism and so confuses his mind.

Scripture does not forbid anything which God has given us for our use; but it condemns immoderation and thoughtless behavior. For instance, it does not forbid us to eat, or to beget children, or to possess material things and to administer them properly. But it does forbid us to be gluttonous, to fornicate and so on. It does not forbid us to think of these things — they were made to be thought of —  but it forbids us to think of them with passion [by which I think he means with a grasping possessiveness that puts those things in place of God as opposed to enjoying them as gifts from and a means for enjoying God].

– Four Hundred Texts on Love, Fourth Century

Previously from the Philokalia: Preoccupation with Material Things