“What is the name that ‘the whole family in heaven and earth is named’ after in Ephesians 3:15?”
“For this cause I bow my knees unto the Father of our Lord Jesus Christ, Of whom the whole family in heaven and earth is named” (Eph. 3:14-15).
The previous verse (Eph. 3:14) provides us with the answer to this question. The name is “our Lord Jesus Christ.” Ephesians teaches the precious, magnificent truth of believers being “in Christ” (Eph. 1:3; 2:6,13). The moment we trust the gospel of salvation, we are placed into Christ by the Holy Spirit. As members of His Body, we are united with Christ and His name. In our Savior’s exaltation, He is “Far above… every name that is named” (Eph. 1:21). And we are one with Him, joined to His life eternal, resurrection power, seated position, and exalted name (1:17-23).
Paul wrote that the “whole family in heaven and earth” is named after Christ. The “whole family” is the entire family of God. In this epistle, Paul taught about the blessing of believing Gentiles under grace being “no more strangers and foreigners, but fellowcitizens with the saints, and of the household of God” (2:19). We have been born by the Spirit into “the household,” or the family, “of God.”
“Heaven and earth” are the two places you can currently find the whole family of God. Part of the family is already home in heaven, and the rest of the family is here on earth, representing Christ to this world as His ambassadors (2 Cor. 5:20). We are all one in Christ; we belong completely to Him, and we are one with His name: “our Lord Jesus Christ.” source