“We”, in this case denoting us, the Saints of God.
“Body”, denoting – “A group of individuals regarded as an entity;” (FD)
“Of Christ”, denoting – “belonging to” Christ, who is the head in whom we all are joined in. (CD)
The body of Christ is fitly joined together
Fitly – We are here, “in a proper manner or place, or at a proper time” – (FD)
Joined – connected – “fastened together” – to one another – (CD)
Paul urges us to do the following:
1 Therefore I, the prisoner for the Lord, I urge you to,
walk worthy of the calling you have received, 2 with all humility and gentleness, with patience, accepting, one another in love, 3 diligently keeping the unity of the Spirit with the peace that binds us.
Remembering and understanding that,
4 There is (only) one body and one Spirit — just as you were called to one hope, l at your calling — 5 one Lord, one faith, one baptism, 6 one God and Father of all, who is above all and through all and in all.
11 And He personally gave some to be apostles, some prophets, some evangelists, some pastors and teachers, 12 for the training of the saints in the work of ministry, to build up the body of Christ, 13 until we all reach unity in the faith and in the knowledge of God’s Son, growing into a mature man with a stature measured by Christ’s fullness.
14 Then we will no longer be little children, tossed by the waves and blown around by every wind of teaching, by human cunning with cleverness in the techniques of deceit. 15 But speaking the truth in love, let us grow in every way into Him who is the head — Christ.
16 From Him the whole body, fitted and knit together by every supporting ligament, promotes the growth of the body for building up itself in love by the proper working of each individual part.
Definitions are from the Free Dictionary (FD) and Cambridge Dictionary (CD)
Bible Verses from The Holman Christian Standard Bible (HCSB)