Paul refers to all the believers in Christ as if they were different parts of the human body. He does this to illustrate that although believers may serve Christ in different ways, each person belongs to Christ and serves in an important way. (See: [[rc://en/ta/man/translate/figs-metaphor]])
Paul speaks of the believers as if God had physically joined them together like the parts of the human body. You can translate this in an active form. AT: "God has joined each believer together with all other believers" (See: [[rc://en/ta/man/translate/figs-metaphor]] and [[rc://en/ta/man/translate/figs-activepassive]])