Psalms 2:7 - Coke's Commentary on the Holy Bible

I will declare the decree— Or, I will tell of a decree. David having introduced God as declaring that he would speak to the confusion of his enemies, and convince them that he had made him king in Sion, further says, for the encouragement of his subjects, that he would relate to them God's purpose concerning him, and the gracious assurances that he had been pleased to grant him. The decree concerning David was this: Thou art my son, &c. God himself was properly king over Israel; Psalms 89:18. David styles him, his God, and his king; Psalms 68:24 but he declared concerning David, Thou art my son.—I will make him my first-born; Psalms 89:27 namely, by giving him the rights of primogeniture, and advancing him as such to the kingdom. Kings in general, and magistrates, are styled gods, and sons of the Most High, in scripture; Ps. lxxxii, 1. 6 and by profane writers. See Callim. Hymn. in Jov. v. 80. But there is a peculiar propriety in this expression, Thou art my son, as used of David; because God did, in a great measure, by fixing him on the throne, and making it hereditary in his family, cede and transfer the kingdom and government, which were originally in himself, to David and his posterity; hereby making him, as it were, his son and successor in the kingdom. When God adds, I have begotten thee, it is not another expression denoting the same as thou art my son, but implies his being made son and heir by adoption. This description to denote the adoption of any person by, and his copartnership with another in, or succession to his kingdom, is not peculiar to the sacred writings. See Pliny's Panegyric on Trajan, cap. 6, 7, &c. The words this day, I suppose, denote the day in which David received the divine decree or constitution by the hand of Nathan. This I apprehend to be the literal meaning of the words, as they belong to David in person; but as they belong to him in his most illustrious successor, they have yet a nobler meaning. They are cited by St. Paul, in his sermon to the Jews at Antioch, as predictive of the resurrection of Christ; and by the author to the Hebrews applied to him as a proof of his being made better, that is, exalted to higher honour and dignity than the angels, by his resurrection and endless life. Hebrews 1:5. God, having declared him to be his Son with power, by his resurrection from the dead, and session at the right hand of the Majesty on high. See Romans 1:4 and Acts 4:25 which contains a full proof that this Psalm was written by David.