The moment by which the whole pre-messianic period was completed. Comp. Eph 1:10. It answers to the time appointed of the Father (Gal 4:2). For πλήρωμα see on Joh 1:16. The meaning of the word is habitually passive - that which is completed, full complement. There are frequent instances of its use with the genitive, as “fullness of the earth, blessing, time, the sea, Christ,” in all which it denotes the plenitude or completeness which characterizes the nouns.
Sent forth (ἐξαπέστειλεν)
From himself: from his heavenly glory. This does not mean that God then, for the first time, embodied what had previously been a mere ideal, but that he sent forth a preexisting person. See Phi 2:6.
Made of a woman (γενόμενον)
Or born. Repeated, and expressing the fact that Christ became a man, as distinguished from his prehistoric form of being.
Under the law
The earthly being of Christ began under the law. He was not only of human birth, but of Jewish birth; subjected to all the ordinances of the law, as circumcision for instance, like any other Jewish boy.