How is the church today described in relation to Christ's headship?
The church today is described as a called-out assembly whose head is in heaven, namely Christ as the head of the body, with believers composing that body. This distinguishes it from Peter's Acts ministry, which makes no mention that Christ is head of this called-out assembly or that they are part of Him.
Les explains that the same Greek word Ecclesia can describe a called-out assembly, but the church today carries a new connotation in Paul's writings: it is the church which is His body, or the body which is the church. What qualifies it is that its head is in heaven as the head of the body, and believers are the body. Les contrasts this with Peter in Acts, noting that Peter never teaches that Christ is the head of this called-out assembly or that they are part of Him. He emphasizes that it is just as important to see what Scripture does not say as what it does say. In 1 Corinthians 12:12, Paul uses the human body—one body with many members—to illustrate that all the members, though many, are one body, and so also is Christ, referring to the Church which is His body.