Commentary on Psalm 1. Athanasios the Great

-St. Athanasios the Great
Psalm of David
David lays the foundation for a prophecy concerning Christ, who was to be born of his lineage. Therefore, he first blesses those who place their hope in Him. He calls blessed those who have not walked “in the counsel of the ungodly,” nor stood “on the path of sinners,” nor sat “in the seat of the pestilent.” For among the Jews, three groups rose against the Savior: the scribes, the Pharisees, and the lawyers, who are justly named the ungodly, sinners, and pestilent. The “path” signifies life, for it leads those born to their end.
Blessed is the man that went not unto the counsel of the ungodly
The “counsel of the ungodly” may be understood as the assembly or gathering of deceitful people. Since associating with such gatherings is harmful, the psalmist blesses the one who in no way aligns with them. Such was Joseph of Arimathea, who buried the body of the Lord and God; for it is said of him that he “had not consented to the counsel” of those who betrayed Jesus (Luke 23:51). …”nor sat in the seat of the pestilent.” By “seat” is meant teaching, as it is said: “in Moses’ seat” (Matt. 23:2). Therefore, the seat of the pestilent is the teaching of the deceitful.
But his will is in the law of the Lord, and on his law doth he meditate day and night.
The “law” here is, of course, the divine law. This expresses unwavering zeal, for one must not meditate on the Lord’s law with negligence, nor intermittently, but must always and continually be devoted to the words of God. This is conveyed by the phrase “day and night.” The reward for such good work is beautiful. For he who engages in the study of God’s law is refreshed by its streams. Christ Himself called His teaching water, saying: “If any man thirst, let him come unto Me, and drink” (John 7:37). The one who meditates on the law is likened to a tree by the waters, ever flourishing and always abounding in timely fruits. For the practitioners of virtue, though they will bear the fruits of their labors in the future, are even now shaded, as it were, by leaves of good hope, and the weight of their labors is covered with spiritual delight. Such a one “in all things… shall prosper.” For he who conforms his will to the will of the law will do nothing contrary to God’s commandments. The psalmist, having first forbidden all forms of vice and shown the perfection of divine laws, then adds: “all things, whatsoever he doeth.”
And he shall be like a tree planted by flowing waters
In inspired Scripture, Christ is depicted as a tree of confession, as it is said: “She is a tree of life to them that lay hold upon her” (Prov. 3:18). Therefore, the psalmist says that those who believe in Christ will be His body. For “He shall change our vile body, that it may be fashioned like unto His glorious body” (Phil. 3:21). The “flowing waters” signify the divine Scriptures, in which Christ is proclaimed everywhere. Christ is the tree of life; the Apostles are the branches; the blood and water from Christ’s side are the fruit, with the blood representing His suffering and the water signifying baptism; His words are the leaves. “which shall give his fruit in his time.” By the fruit of the tree, understand true faith; by its leaves, the fulfillment of the commandments. The fruit is those who are saved; the root is baptism; the husbandman is the Father. “And his leaf shall not fall, and all whatsoever he doeth shall prosper.” For a work done according to God cannot be unprofitable. “The time of giving” depends on the one who receives.
Therefore the ungodly shall not rise at the judgment
Because they have no root, they are like dust of the earth, blown about by the wind. By “wind,” understand the fearful proclamation of God: “Depart from Me, ye cursed, into everlasting fire” (Matt. 25:41). Those who hear this voice will not stand but will fall, for they are not established in Christ, who is the support and foundation of the faithful. For it is said “at the judgment,” not at an inquiry. The psalmist adds: “in the counsel of the righteous,” for he separates the righteous from the sinners.
For the Lord knoweth the way of the righteous
It is said “knoweth” instead of “honors,” as God said to Moses: “I know thee above all” (Exod. 33:12), meaning “I prefer thee, and thou hast found grace in My sight.” source