{And certain men came down from Judea} (kai tines
katelthontes apo t(8873) Ioudaias). Evidently the party of the
circumcision in the church in Jerusalem ( 11:2 ) had heard of the
spread of the gospel among the Gentiles in Cyprus, Pamphylia, and
South Galatia (Phrygia, Pisidia, Lycaonia). Possibly John Mark
after his desertion at Perga ( 13:13 ) told of this as one of his
reasons for coming home. At any rate echoes of the jubilation in
Antioch in Syria would be certain to reach Jerusalem. The
Judaizers in Jerusalem, who insisted that all the Gentile
Christians must become Jews also, had acquiesced in the case of
Cornelius and his group ( 11:1-18 ) after plain proof by Peter
that it was the Lord's doing. But they had not agreed to a formal
campaign to turn the exception into the rule and to make
Christianity mainly Gentile with a few Jews instead of mainly
Jewish with a few Gentiles. Since Paul and Barnabas did not come
up to Jerusalem, the leaders among the Judaizers decided to go
down to Antioch and attack Paul and Barnabas there. They had
volunteered to go without church action in Jerusalem for their
activity is disclaimed by the conference ( Ac 15:24 ). In  Ga
2:4  Paul with some heat describes these Judaizers as "false
brethren, secretly introduced who sneaked in to spy out our
liberty." It is reasonably certain that this visit to Jerusalem
described in  Ga 2:1-10  is the same one as the Jerusalem
Conference in Acts  15:5-29  in spite of the effort of Ramsay to
identify it with that in  11:29f . Paul in Galatians is not
giving a list of his visits to Jerusalem. He is showing his
independence of the twelve apostles and his equality with them.
He did not see them in  11:29f. , but only "the elders." In  Ac
15  Luke gives the outward narrative of events, in  Ga 2:1-10 
Paul shows us the private interview with the apostles when they
agreed on their line of conduct toward the Judaizers. In  Ga 2:2 
by the use of "them" (autois) Paul seems to refer to the first
public meeting in Acts before the private interview that came in
between verses  15:5-6 . If we recall the difficulty that Peter
had on the subject of preaching the gospel to the heathen
( 10:1-11:18 ), we can the better understand the attitude of the
Judaizers. They were men of sincere convictions without a doubt,
but they were obscurantists and unable and unwilling to receive
new light from the Lord on a matter that involved their racial
and social prejudices. They recalled that Jesus himself had been
circumcised and that he had said to the Syro-Phoenician woman
that he had come only save to the lost sheep of the house of
Israel ( Mt 15:24ff. ). They argued that Christ had not repealed
circumcision. So one of the great religious controversies of all
time was begun, that between spiritual religion and ritualistic
or ceremonial religion. It is with us yet with baptism taking the
place of circumcision. These self-appointed champions of
circumcision for Gentile Christians were deeply in earnest.
{Taught the brethren} (edidaskon tous adelphous). Inchoative
imperfect active, began to teach and kept it up. Their attitude
was one of supercilious superiority. They probably resented the
conduct of Barnabas, who, when sent by the Church in Jerusalem to
investigate the conversion of the Greeks in Antioch ( 11:20-26 ),
did not return and report till a strong church had been
established there with the help of Saul and only then with a big
collection to confuse the issue. Paul and Barnabas were on hand,
but the Judaizers persisted in their efforts to force their views
on the church in Antioch. It was a crisis. {Except ye be
circumcised after the custom of Moses, ye cannot be saved} (ean
me peritm(8874)h(8874)e t(9369) ethei M(9375)se(9373), ou dunasthe s(9374)h(886e)ai). There
was the dictum of the Judaizers to the Gentiles. Paul and
Barnabas had been circumcised. This is probably the precise
language employed, for they spoke in Greek to these Greeks. It is
a condition of the third class (undetermined, but with prospect
of being determined, ean plus the first aorist passive
subjunctive of peritemn(935c)). There was thus hope held out for
them, but only on condition that they be circumcised. The issue
was sharply drawn. The associative instrumental case (	(9369)
ethei) is customary. "Saved" (s(9374)h(886e)ai) here is the Messianic
salvation. This doctrine denied the efficacy of the work of
Christ.