Matthew Poole and continuators on Romans 1:3

3. Concerning his Son Jesus Christ our Lord, which was made of the seed of David according to the flesh.

This Phrase either respects the Holy Scriptures, mentioned immediately before in the second Verse▪ the Sum and Substance of them, is, concerning the Messiah, the Son of God: Or else: it respects the Gospel▪ that was spoken of in the first Verse; the second Verse being only a Parenthesis, as was before hinted; then the meaning is, That the Apostle Paul was separated to the Gospel of God, which only or mainly concerns his Son Jesus Christ. And this seems to shew the Excellency of the Gospel, that it doth not Treat of vulgar and ordinary Matters, as of the Gods of the Gentiles, or the Actions of Alexander, Caesar ▪ the Scipio's, or such like Heroes; but of the Son of God himself.

i. e. As he afterwards Expresseth it, according to the Flesh or his Humane Nature; in regard of his Divine Subsistence, He was begotten and not made; in regard of his Manhood, He was made and not begotten. When he sayes the Son of God was Made, &c. it is undeniably imply'd, That he did Exist before his Incarnation, and was the Son of God before He was the Son of Man. This Place proves clearly these two Truths; 1. That in the Person of Jesus Christ there are two Natures. 2. That there is betwixt these, a Communication of Properties; here the Son of God is said to be made of the Seed of David; and elsewhere the Son of Man is said to have come down from Heaven, vid. Iohn 3.13. compare Iohn 6.62. Act. 20.28. 1 Cor. 2 8.

i. e. of the Virgin Mary, which was of David's Lineage and Posterity; the Promise was expressly, That the Messiah should be of the Fruit of his Loynes, Act. 2.30. compared with Isa. 11.1. Ier. 23.5. Ezek. 34.24. Yea, this Promise was so fully known to the Jews, that when they spake of the Messiah, they call'd Him the Son of David, vid. Mat. 22.42. and 21.9. Mar. 10.47.48. Iohn 7.42. Hence 'tis that the Evangelists, Matthew and Luke, are so careful and industrious to prove, That the Virgin Mary, and Ioseph, to whom she was Espoused, did come of David's Line and Race.

Marginal references: Math. 1.6.16.2 Tim. 2.8.