<< Ephesians 1:23

Eph 1:22-23
22 And hath put all things under his feet, and gave him to be the head over all things to the church,
23 Which is his body, the fulness of him that filleth all in all.
KJV
 

Eph 1:22-23
22 God has put everything under his feet, and has made him the head over all things to the church. 23 They are his body, the fullness of him who fills all in all.
ELG

In speaking to the Ephesian Christians, Paul made sure they understood Jesus Christ as being the head over all things to the church.  He also informed them that the church is His body.  It is His possession which is set forth by Christ Himself when He told Peter that "upon this rock I will build my church," (Matt 16:18). 

Paul really expounded on the relationship between Christ and what He means to earth and His church in his letter to the Colossians; 

Col 1:16-18
16 For by him were all things created, that are in heaven, and that are in earth, visible and invisible, whether they be thrones, or dominions, or principalities, or powers: all things were created by him, and for him:
17 And he is before all things, and by him all things consist.
18 And he is the head of the body, the church: who is the beginning, the firstborn from the dead; that in all things he might have the preeminence.

Paul further referred to this relationship later in Ephesians.

Eph 5:23-24
23 For the husband is the head of the wife, even as Christ is the head of the church: and he is the saviour of the body.
24 Therefore as the church is subject unto Christ, so let the wives be to their own husbands in every thing.

Let Paul speak for himself. 

"the fulness of him that filleth all in all"

The fulness of him [Christ] that fills everything in everybody.

The church is the body of Christ.  He is the head of the body.  The body of Christ is the totality of all the faithful Christians since the dawn of time.  Jesus Christ is set forth as being the governing power of a singular body of Christians.  There are many congregations of Christians, but only one body of Christ. 

Eph 4:4
There is one body, and one Spirit, even as ye are called in one hope of your calling;
KJV

See Also:  (Eph 5:25-30, Rom 12:5, 1 Cor 12:12, 1 Cor 12:27)

KJV with Strong's Numbers

<< Ephesians 1:23