They have been informed concerning thee (kathchqhsan peri sou). First aorist passive indicative of kathcew. A word in the ancient Greek, but a few examples survive in the papyri. It means to sound (echo, from hcw, our word) down (kata), to resound, re-echo, to teach orally. Oriental students today (Arabs learning the Koran) often study aloud. In the N.T. only in Luke 1:4 which see; Acts 18:25 ; Acts 21:21 ; 1 Corinthians 14:19 ; Galatians 6:6 ; Romans 2:18 . This oral teaching about Paul was done diligently by the Judaizers who had raised trouble against Peter ( Acts 11:2 ) and Paul ( Acts 15:1Acts 15:5 ). They had failed in their attacks on Paul's world campaigns. Now they try to undermine him at home. In Paul's long absence from Jerusalem, since Acts 18:22 , they have had a free hand, save what opposition James would give, and have had great success in prejudicing the Jerusalem Christians against Paul. So James, in the presence of the other elders and probably at their suggestion, feels called upon to tell Paul the actual situation. That thou teachest all the Jews which are among the Gentiles to forsake Moses (oti apostasian didaskei apo Mwusew tou kata ta eqnh panta Ioudaiou). Two accusatives with didaskei (verb of teaching) according to rule. Literally, "That thou art teaching all the Jews among (kata) the Gentiles (the Jews of the dispersion as in Acts 2:9 ) apostasy from Moses." That is the point, the dreadful word apostasian (our apostasy), a late form (I Macc. 2:15) for the earlier apostasi (cf. 2 Thessalonians 2:3 for apostasia). "In the eyes of the church at Jerusalem this was a far more serious matter than the previous question at the Conference about the status of Gentile converts" (Furneaux). Paul had brought that issue to the Jerusalem Conference because of the contention of the Judaizers. But here it is not the Judaizers, but the elders of the church with James as their spokesman on behalf of the church as a whole. They do not believe this false charge, but they wish Paul to set it straight. Paul had made his position clear in his Epistles (I Corinthians, Galatians, Romans) for all who cared to know. Telling them not to circumcise their children (legwn mh peritemnein autou ta tekna). The participle legwn agrees with "thou" (Paul), the subject of didaskei. This is not indirect assertion, but indirect command, hence the negative mh instead of ou with the infinitive (Robertson, Grammar, p.1046). The point is not that Paul stated what the Jewish Christians in the dispersion do, but that he says that they (autou accusative of general reference) are not to go on circumcising (peritemnein, present active infinitive) their children. Paul taught the very opposite ( 1 Corinthians 7:18 ) and had Timothy circumcised ( Acts 16:3 ) because he was half Jew and half Greek. His own practice is stated in 1 Corinthians 9:19 ("to the Jews as a Jew"). Neither to walk after the customs (mhde toi eqesin peripatein). Locative case with infinitive peripatein. The charge was here enlarged to cover it all and to make Paul out an enemy of Jewish life and teachings. That same charge had been made against Stephen when young Saul (Paul) was the leader ( 1 Corinthians 6:14 ): "Will change the customs (eqh the very word used here) which Moses delivered unto us." It actually seemed that some of the Jews cared more for Moses than for God ( Acts 6:11 ). So much for the charge of the Judaizers.