In St. Gregory of Nyssa’s works there is a beautiful, little known work. This is his commentary on The Inscriptions of the psalms (we probably miss these as we read but these are the texts, some small some large, written in tiny font above the Psalm in most of our Bibles). He sees these inscriptions as leading us to the underlying skopos (intent or end, sort of like ‘scope’ in English) of the Psalter. The text of the Psalms is, for St. Gregory of Nyssa, the stages of the spiritual life. He comments that the first part of the Psalter instructs us on returning from evil and returning to God. Here he comments on what this looks like, that we become as He is.
“The person, therefore, who has been initiated into the life in virtue in the first part of the Psalter, and has discovered how sweet that which is desired tastes, and has consumed every creeping form of desire in himself, and with the teeth of self-control has devoured the passions in place of creatures, thirsts for participation in God more than ‘the hart’ longs for ‘the fountains of water’ Ps 41.2 . And it follows that the person who finds the fountain after this excessive thirst draws in as much water as the abundance of his desire draws off. But he who has received what he desired in himself is full of what he desired. For that which has become full is not again emptied on the model of physical satiety, nor does that which was drunk remain inactive in itself. In whomever the divine fountain has come into existence, it transforms the one who has embraced it to itself, and imparts to this person a portion of its own power.” St. Gregory of Nyssa, Commentary on the Inscriptions of The Psalms, Part 1, Chapter 5. (can be purchased here: Gregory of Nyssa, On The Inscriptions of The Psalms).