For I bear them record, that they have a zeal of
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 a zealot as any of them all. But now whilst the apostle is expressing his strong affection for this people, he is careful to act the faithful part to them, and points out their mistakes, and shows them their faults; which he does in this and the following verse, by observing, that they had a zeal of God indeed,
but not according to knowledge:
it was not well regulated, it proceeded on mistaken principles, and moved in a wrong way, in persecuting the church of God, in doing things contrary to the name of Christ, in putting to death his ministers and members, thinking that hereby they did God good service; which arose from their ignorance of their Father, and of the Son: though they had a zeal of God, they knew neither God nor Christ aright; they did not know God in Christ, nor Jesus to be the true Messiah; they understood neither law nor Gospel truly, and fancied the Gospel was contrary to the law, and an enemy to it; and therefore in their great zeal opposed it, and the professors of it; they were zealous of the law, and of doing the commands of it, but knew not the true nature, use, and end of the law; as appears by what follows.