{Because they feared the Jews} (hoti ephobounto tous
Ioudaious). Imperfect middle, a continuing fear and not without
reason. See already the whispers about Jesus because of fear of
the Jews ( 7:13 ). {Had agreed already} ((8864)(8820)sunetetheinto).
Past perfect middle of suntith(886d)i, to put together, to form a
compact ( 7:32,47-49 ). {If any man should confess him to be
Christ} (ean tis auton homolog(8873)(8869) Christon). Condition of
third class with ean and first aorist active subjunctive of
homologe(935c) and predicate accusative Christon. Jesus had made
confession of himself before men the test of discipleship and
denial the disproof ( Mt 10:32  Lu 12:8 ). We know that many of
the rulers nominally believed on Jesus ( 12:42 ) and yet "did not
confess him because of the Pharisees" (alla dia tous Pharisaious
ouch h(936d)ologoun), for the very reason given here, "that they
might not be put out of the synagogue" (hina m(8820)aposunag(9367)oi
gen(936e)tai). Small wonder then that here the parents cowered a
bit. {That he should be put out of the synagogue} (hina
aposunag(9367)os gen(8874)ai). Sub-final use of hina with second
aorist middle subjunctive of ginomai. Aposunag(9367)os (apo and
sunag(9367)(885c)) is found in N.T. only here and  12:42  16:2 . A
purely Jewish word naturally. There were three kinds of
excommunication (for thirty days, for thirty more, indefinitely).