How long is Christ to sit at the Father's right hand?

Christ is to sit at the Father's right hand until the Father makes His enemies His footstool. This period continues while Satan remains the god of this world and is not yet under Christ's feet. The context indicates the session lasts until that final subjection occurs.

Les explains that even after Christ was raised victoriously over a defeated Satan, Satan is still the god of this world, still destroying lives, and is not yet under Christ's feet. Therefore, Christ is to sit at the Father's right hand until the Father makes His enemies His footstool. Les also directs attention to Hebrews chapter 1, where Christ has accomplished the work of the cross and has risen from the dead, with the full subjection of enemies still awaited.

Psalms 110:1

The LORD said unto my Lord, Sit thou at my right hand, until I make thine enemies thy footstool.

What does it mean that Christ sits at the Father's right hand until his enemies are made his footstool?

Christ's sitting at the Father's right hand denotes His completed work and present exaltation, but it also marks a waiting period. Though Satan was defeated potentially at the cross, he remains the god of this world, not yet under Christ's feet. The Father will make enemies His footstool.