{But because of the false brethren privately brought in}
(dia de tous pareisaktous pseudadelphous). Late verbal
adjective pareisaktos from the double compound verb
pareisag(935c), found in papyri in the sense of brought in by the
side or on the sly as here. Evidently some of the Judaizers or
sympathizers whom Paul had not invited had come in as often
happens. Paul terms them "false brethren" like "the false
apostles" in  2Co 11:13  of the Judaizers in Corinth. {Who came
in privily} (hoitines pareis(886c)thon). Repetition of the charge
of their slipping in unwanted (pareiserchomai, late double
compound, in Plutarch, in N.T. only here and  Ro 5:20 ). {To spy
out} (kataskop(8873)ai). First aorist active infinitive of
kataskope(935c), old Greek verb from kataskopos, a spy, to
reconnoitre, to make a treacherous investigation. {That they
might bring us into bondage} (hina h(886d)as katadoul(9373)ousin).
Future active indicative of this old compound, to enslave
completely (kata-) as in  2Co 11:20 . Nowhere else in N.T. This
was their purpose (hina and future active indicative of this
causative verb). It was as serious a conflict as this. Spiritual
liberty or spiritual bondage, which?