Romans 12:4-5

⁴ For as we have many members in one body, but all the members do not have the same function,

⁵ so we, being many, are one body in Christ, and individually members of one another.

Paul is talking about unity and harmony — and diversity of functions

function (office) — not a position but a function. The same word is translated “deeds” in Romans 8:13.

We are a common body because of our unity in Christ.

1 Corinthians 12:12 — For as the body is one and has many members, but all the members of that one body, being many, are one body, so also is Christ.