Psalms 52:8

But what shall they then say that shall laugh? "And over him they shall laugh; and shall say, Behold a man that hath not set God for his helper" (ver. 8). See ye the body earthly! "As much as thou shalt have, so great shalt thou be," is a proverb of covetous men, of grasping men, of men oppressing the innocent, of men seizing upon other men's goods, of men denying things entrusted to their care. Of what sort is this proverb? "As much as thou shalt have, so great shalt thou be;" that is, as much as thou shall have had of money, as much as thou shalt have gotten, by so much the more mighty shall thou be. "Behold a man that hath not set God for his helper, but hath trusted in the multitude of his riches." Let not a poor man, one perchance that is evil, say, I am not of this body. For he hath heard the Prophet saying, "He hath trusted in the multitude of his riches:" forthwith if he is poor, he heedeth his rags, he hath observed near him perchance a rich man among the people of God more richly apparelled, and he saith in his heart, Of this man he speaketh; doth he speak of me? Do not thence except thyself, do not separate thyself, unless thou shalt have seen and feared, in order that thou mayest hereafter laugh. For what doth it profit thee, if thou dost want means, and thou burnest with cupidity? […]

From what I have said already, we have learned what sort of end the one who is powerful in wickedness will obtain. But as for me, says David, since I have been taught this by the Holy Spirit, I would never be exalted over abundance of wealth, nor over the vanity of mortal life. For "vanity of vanities, all is vanity." But also, as I flee from the path of the one who is powerful in wickedness, I would not sharpen my tongue and my words for the destruction of others, but rather for the benefit of souls and the service of the words of salvation. And in my other actions too, I would become so flourishing and fruitful that my soul would be compared with an ever-flourishing and richly fruitful plant that has been planted in the house of God. For this reason, I say: "But I am like a fruitful olive tree in the house of God"—or, according to Symmachus' translation: "But I am like a flourishing olive tree in the house of God." For I did not turn away at all from the house of God; rather, after being planted inside it, as it were in God's own garden, and while enjoying the streams of the spring in the house of God, I became richly fruitful and ever-flourishing, in accordance with the pattern of the planted olive tree that has been received among the ever-flourishing [plants]. But observe that when David said this, he was not in Jerusalem, which the Jewish people considered to be the house of God—for it had not yet been built; and neither was he in the tabernacle built by Moses, which did still exist at that time among the Jews. For when he was fleeing from Saul, he passed his time among others—and yet he did indeed know that he had been planted in the house of God, since he understood the "house of God" to be the pious way of life. […]

You are being armed not with perishable but with spiritual weapons. The paradise in which you are being planted is the soul's paradise, wherein you will be named with a name you did not have before. You were a catechumen till now, but now you are to be called believer. Henceforth you are transplanted among the olives of that paradise or are being grafted on a good olive tree being taken from a wild olive. You pass from sins to righteousness, from defilements to purity. You are becoming part of the holy Vine. If, then, you abide in the Vine, you grow into a fruitful branch; but if you do not so abide, you will be burned up in the fire. Let us therefore bring forth worthy fruit. For let not that come about, that there should happen to us what happened to the barren fig tree in the Gospel. Let not Jesus come in these days and utter the curse on the fruitless; instead may all of you say, "I am like a green olive tree in the house of God; my trust is in the tender mercy of God, forever and ever"; not a material olive tree but a spiritual and glorious one. It is God who plants and waters, but it is yours to bear fruit; God's to bestow the gift, and yours to receive it and keep it forever. But do not esteem the gift lightly because it is given freely. Rather, receive it reverently and guard it with care.

But do you want me to show you from the Scriptures that trees or wood are given the name of individual virtues, which we mentioned above? I turn to the most wise Solomon as a witness when he said about wisdom, "The tree of life is for all who embrace it." Therefore, if "wisdom is the tree of life," without a doubt, there is another tree of prudence, another of knowledge and another of justice.

"But I am like a fruitful olive tree." Here he treats of the holiness of the good. And first he shows what they do in the present. Second, what they promise, at "I will praise you." The saints do a twofold good in the present …