Isa 55:10

“For the rain and the snow do not return to heaven but accomplish in the earth the will of him that sends them. So the word that he shall send through his Christ, who is himself the Word and the Message, shall return to him with great power. For when he shall come and bring it, he shall come down like rain and snow, and through him all that is sown shall spring up and bear righteous fruit, and the word shall return to his sender; but not in vain shall his going have been, but thus shall he say in the presence of his sender, "Behold, I and the children that the Lord has given me." And this is the voice through which the dead shall live. And this is the voice of God that shall sound from on high and raise up all the dead.”

“(Verse 10, 11) And how does rain and snow descend from the sky, and it will not return there until it has soaked the earth and makes it bring forth and sprout, giving seed to the sower and bread for eating. So shall my word be that goes out from my mouth; it will not return to me empty, but it will accomplish what I desire, and it will succeed in the purpose for which I sent it. LXX: Just as the rain and snow descend from the sky and do not return until they have soaked the earth, causing it to bring forth and sprout, giving seed to the sower and bread for eating. So shall my word be that comes out of my mouth; it will not return until it accomplishes what I desire, and I will make its ways prosperous and fulfill my commands. Based on what has been said earlier, the meaning here is briefly: may the people of the nations not be incredulous, that after so many wicked deeds the impious may suddenly be saved. For my thoughts are not the same as human thoughts, and as far as the heavens are from the earth, so are my thoughts separated from human thoughts. For I am most merciful and abundant in forgiving. Would you like to hear another similarity? Just as rain and snow descend from the sky and do not return there but drench the earth, and make it bring forth and sprout, giving seed to the sower and bread to the eater, so shall my word be that goes forth from my mouth; it shall not return to me empty, but it shall accomplish what I purpose, and shall succeed in the thing for which I sent it. According to the twofold interpretation of anagoge, the word of the Lord can refer to that one of whom it is written: In the beginning was the Word, and the Word was with God, and the Word was God (John 1:1). He who does not turn to him empty, unless he has done the will of the Father; and has completed all things for which he was incarnate, and has reconciled the world to God. He who is said to come forth from the mouth, and from the womb and birth canal: not that God has these members, but that we learn the nature of the Lord through our words. Or certainly this must be said, that the sermon of the Gospel doctrine is called a shower, and the rains that are poured out upon good earth, spiritual clouds, to which the truth of God reaches. In the book of Deuteronomy, Moses promises rain and showers, saying: Let the earth hear the words of my mouth; let my speech come down as the rain and the dew, so that those who sow in tears may reap in joy. And those who sow in righteousness and in the spirit will reap the fruit of eternal life, receiving the bread of the Gospel teaching, as it is written in Proverbs and Ecclesiastes: Open your eyes and be filled with bread. And again: Cast your bread upon the waters, for you will find it after many days. For it is not to be believed that it is commanded to those who eat, that they should open their eyes to eat this bread, by which bodies are nourished, and thus be satisfied with bread, which the poor secretly eat in Abacuc (Abac. III). But God's teaching encourages us to the bread of doctrine, which we cannot eat unless we open the eyes of our heart. Of whom Paul often writes to these, who are nourished by the words of faith and truth (II Cor. IX). And it is commanded to the teacher, that he may send the bread of his doctrine over all the water, and pour out spiritual grace upon all, and know that if he does what is commanded, he will receive rewards in the last time. And it will seem unjust that the one who gives alms should make friends for himself from unjust mammon, who will receive him into eternal tabernacles (Luke XVI): and the one who gives spiritual food and gives food to his servants in their time, will not find them after many ages, which Ecclesiastes calls the multitude of days (Ecclesiastes XI).”

“By means of diffusion, as of brightness out of light, of heat out of fire, of a river out of its headspring, of rain out of a full or humid cloud. In the first diffusion, equality is lacking, for brightness is not the same as light. In the second, closeness is lacking, for heat is not close to fire, since it is the principle neither of its form nor of its origin, but is merely an accident. In the third, simultaneity is lacking, for a spring diffuses itself by flowing, and not all at once. In the fourth, fullness is lacking, for not all of the rain is drawn out of a cloud, but only successive drops. Now, join these four conditions to a single diffusion, one of splendor having equality, of heat having closeness and substantiality, of a river or fountain having simultaneity, and of rain having fullness: and in this way, you will have a trace of the eternal generation. Hence, the Son is sometimes compared to brightness: "Being the brightness of His glory," etc.; at other times, to a flame, as in Moses' bush which represented the person of the Son; or again, as a river or spring: "But a spring rose out of the earth. A river rose in Eden." Again, He is sometimes compared to rain: "For just as from the heavens the rain and snow come down and do not return there till they have watered the earth," etc. And, later: "So shall my word be that goes forth from my mouth," that is, from the Father's heart.”