Romans 9:5

Whose are the fathers--here, probably, the three great fathers of the covenant--Abraham, Isaac, and Jacob--by whom God condescended to name Himself (Exo 8:6, Exo 8:13; Luk 20:37). and--most exalted privilege of all, and as such, reserved to the last. of whom as concerning the flesh--(See on Rom 1:3). Christ came--or, "is Christ" who is over all, God--rather, "God over all." blessed for ever. Amen--To get rid of the bright testimony here borne to the supreme divinity of Christ, various expedients have been adopted: (1) To place a period, either after the words "concerning the flesh Christ came," rendering the next clause as a doxology to the Father--"God who is over all be blessed for ever"; or after the word "all"--thus, "Christ came, who is over all: God be blessed.", &c. [ERASMUS, LOCKE, FRITZSCHE, MEYER, JOWETT, &c.]. But it is fatal to this view, as even Socinus admits, that in other Scripture doxologies the word "Blessed" precedes the name of God on whom the blessing is invoked (thus: "Blessed be God," Psa 68:35; "Blessed be the Lord God, the God of Israel," Psa 72:18). Besides, any such doxology here would be "unmeaning and frigid in the extreme"; the sad subject on which he was entering suggesting anything but a doxology, even in connection with Christ's Incarnation [ALFORD]. (2) To transpose the words rendered "who is"; in which case the rendering would be, "whose (that is, the fathers') is Christ according to the flesh" [CRELLIUS, WHISTON, TAYLOR, WHITBY].

— Jamieson-Fausset-Brown Commentary (public domain)