O my soul, thou hast said unto the Lord - The words “O my soul” are not in the original. A literal rendering of the passage would be, “Thou hast said unto the Lord,” etc., leaving something to be supplied. De Wette renders it: “To Yahweh I call; thou art my Lord.” Luther: “I have said to the Lord.” The Latin Vulgate: “Thou, my soul, hast said to the Lord.” The Septuagint: “I have said unto the Lord.” Dr. Horsley: “I have said unto Jehovah.” The speaker evidently is the psalmist; he is describing his feelings toward the Lord, and the idea is equivalent to the expression “I have said unto the Lord.” Some word must necessarily be understood, and our translators have probably expressed the true sense by inserting the words, “O my soul.” the state of mind indicated is that in which one is carefully looking at himself, his own perils, his own ground of hope, and when he finds in himself a ground of just confidence that he has put his trust in God, and in God alone. We have such a form of appeal in Psalms 42:5, Psalms 42:11; Psalms 43:5, “Why art thou cast down, O my soul?”
Thou art my Lord - Thou hast a right to rule over me; or, I acknowledge thee as my Lord, my sovereign. The word here is not Yahweh, but Adonai - a word of more general signification than Yahweh. The sense is, I have acknowledged Yahweh to be my Lord and my God. I receive him and rest upon him as such.
My goodness extendeth not to thee - This passage has been very variously rendered. Prof. Alexander translates it: “My good (is) not besides thee (or, beyond thee);” meaning, as he supposes: “My happiness is not beside thee, independent of, or separable from thee?” So DeWette: “There is no success (or good fortune) to me out of thee.” Others render it: “My goodness is not such as to entitle me to thy regard.” And others, “My happiness is not obligatory or incumbent on thee; thou art not bound to provide for it.” The Latin Vulgate renders it: “My good is not given unless by thee.” Dr. Horsley: “Thou art my good - not besides thee.” I think the meaning is: “My good is nowhere except in thee; I have no source of good of any kind - happiness, hope, life, safety, salvation - but in thee. My good is not without thee.” This accords with the idea in the other member of the sentence, where he acknowledges Yahweh as his Lord; in other words, he found in Yahweh all that is implied in the idea of an object of worship - all that is properly expressed by the notion of a God. He renounced all other gods, and found his happiness - his all - in Yahweh.