μαρτυρω 3140 5719 V-PAI-1S γαρ 1063 CONJ αυτοις 846 P-DPM οτι 3754 CONJ ζηλον 2205 N-ASM θεου 2316 N-GSM εχουσιν 2192 5719 V-PAI-3P αλλ 235 CONJ ου 3756 PRT-N κατ 2596 PREP επιγνωσιν 1922 N-ASF
Vincent's NT Word Studies
2. I bear them record (marturw). Rev. witness. "He seems to be alluding to his conduct of former days, and to say, 'I know something of it, of that zeal'" (Godet).Zeal of God (zhlon Qeou). Rev., zeal for God. Like the phrase "faith of Christ" for "faith in Christ" (Philip. iii. 9); compare Col. ii. 12; Eph. iii. 12; John ii. 17, "the zeal of thine house," i.e., "for thy house." Knowledge (epignwsin). Full or correct and vital knowledge. See on ch. i. 28; iii. 20.
Robertson's NT Word Studies
10:2 {A zeal for God} (zlon qeou). Objective genitive like #Php 3:9, "through faith in Christ" (dia pistews cristou). {But not according to knowledge} (all' ou kat' epignwsin). They had knowledge of God and so were superior to the Gentiles in privilege (#2:9-11), but they sought God in an external way by rules and rites and missed him (#9:30-33). They became zealous for the letter and the form instead of for God himself.