Romans 10:2

“For I bear them record, that they have a zeal of God, etc..] A zeal for God; for the being and unity of God, against the polytheism and idolatry of the Gentiles; for the word of God, the writings of the Old Testament, of which they were zealous defenders and preservers, and which they diligently read and heard explained, and whereby they thought to obtain eternal life; for the law of God, moral and ceremonial, especially for the rituals of the Mosaic economy; for the service and worship of God, they spared no pains, but compassed sea and land to bring in proselytes to their religion; all which the apostle could testify from his own knowledge, and by his own experience, who had been as great…”

“For I bear them record--or, "witness," as he well could from his own sad experience. that they have a zeal of--"for" God, but not according to knowledge--(Compare Act 22:3; Act 26:9-11; Gal 1:13-14). He alludes to this well-meaning of his people, notwithstanding their spiritual blindness, not certainly to excuse their rejection of Christ and rage against His saints, but as some ground of hope regarding them. (See Ti1 1:13).”

“For I bear them record - To bear record means to be a witness; to give evidence. This, Paul was well qualified to do. He had been a Jew of the strictest order Acts 26:5; Philippians 3:5, and he well knew the extraordinary exertions which they put forth to obey the commands of the Law. A zeal of God - A zeal for God. Thus, John 2:17,” The zeal of thine house hath eaten me up;” an earnest desire for the honor of the sanctuary has wholly absorbed my attention; compare Psalms 69:9; Acts 21:20, “Thou seest, brother, how many thousands of Jews there are which believe, and they are all zealous of the law;” Acts 22:3, “And was zealous toward God as ye all are this day.” Zeal for God here means…”

“They have a zeal, but not according to knowledge - They had zeal without knowledge; we have knowledge without zeal. Romans 10:3”

“10:2 Zeal denotes a passionate and commendable commitment to God and his purposes (see Num 25:6-13). But in Paul’s day Jewish zeal was misdirected because it failed to understand that Jesus Christ is the pinnacle of God’s plan. (For Paul’s own misdirected zeal before his conversion to Christ, see Acts 9:1-2; Gal 1:13-14.)”

“I bear them: By this fine apology for the Jews, the Apostle prepares them for the harsher truths which he was about to deliver. Co2 8:3; Gal 4:15; Col 4:13 that they: Kg2 10:16; Joh 16:2; Act 21:20, Act 21:28, Act 22:3, Act 22:22, Act 26:9, Act 26:10; Gal 1:14, Gal 4:17, Gal 4:18; Phi 3:6 but not: Rom 10:3, Rom 9:31, Rom 9:32; Psa 14:4; Pro 19:2; Isa 27:1; Co2 4:4, Co2 4:6; Phi 1:9 Romans 10:3”