“Walk” as a metaphor of general behavior is used in this chapter to admonish Christians to:
(1) walk in love (Ephesians 5:1-2);
(2) walk in the light (Ephesians 5:3-14); and
(3) walk in wisdom (Ephesians 5:15-21). In Ephesians 5:22,
Paul began instructions relative to three classes of reciprocal obligations: (1) those between husbands and wives (Ephesians 5:22-33); (2) those between children and parents (Ephesians 5:6:1-4); and (3) those between servants and masters (Ephesians 5:5-9). Only the first of these is in this chapter.
Be ye therefore imitators of God, as beloved children, and walk in love, even as Christ also loved you, and gave himself up for us, an offering and a sacrifice to God for an odor of a sweet smell. (Ephesians 5:1-2)
Imitators of God …
The New Testament teaches that the only practical revelation of God is that of Christ himself; and, in view of this, “imitating God” is a commandment to be fulfilled by “walking in love,” just as Christ loved us and gave himself for us. Certainly, the teaching here is not to the effect that weak and fallible mortals should in any sense “play God” by usurping to themselves judgments that pertain to God alone.
As Mackay said, “To copy God is to be like a Person, to reflect his image.” Christians should strive to be like God in forbearance, goodness and love.
The reference to Jewish sacrifices in Ephesians 5:2 has puzzled commentators who have variously understood the nature of Christ’s sacrifice (as mentioned here) to be “a sacrifice of consecration (Exodus 29), a peace-offering (Leviticus 3) or a sin-offering (Leviticus 4).” Alfred Barry has presented a very interesting and convincing argument based on a similar expression in Hebrews 10:5, and the Old Testament reference there, and upon the peculiar Hebrew usage of these terms, concluding that,
“Therefore, we have here a complete summary – all the more striking and characteristic because incidental – of the doctrine of the Atonement.” Christ was not merely one kind of sacrifice, or offering, but every kind.
 John Mackay, God’s Order (New York: The Macmillan Company, 1953), p. 170.
 John William Russell, Compact Commentary on the New Testament (Grand Rapids, Michigan: Baker Book House, 1964), p. 481.
 Alfred Barry, Ellicott’s Commentary on the Holy Bible, Vol. XIII (Grand Rapids, Michigan: Zondervan Publishing House, 1959), p. 46.