For - “Because.” Their “philosophy” (Col 2:8) is not “after Christ,” as all true philosophy is, everything which comes not from, and tends not to, Him, being a delusion; “For in Him (alone) dwelleth” as in a temple, etc.
the fulness - (Col 1:19; Joh 14:10).
of the Godhead - The Greek (theotes) means the ESSENCE and NATURE of the Godhead, not merely the divine perfections and attributes of Divinity (Greek, “theiotes”). He, as man, was not merely God-like, but in the fullest sense, God.
bodily - not merely as before His incarnation, but now “bodily in Him” as the incarnate word (Joh 1:14, Joh 1:18). Believers, by union with Him, partake of His fullness of the divine nature (Joh 1:16; 2Pe 1:4; see on Eph 3:19).