Some believe that Christ stood between the elders and the Father who sat on the throne. Here is the mediatorial work of our Lord. As the God man, He mediates between God and redeemed men. He is our go-between. In the Bible horns are a symbol of power.
Kings are people with power.
The seven horns on the Lamb are symbolic of power, and joined with the number seven it means complete and perfect power. This can only be said of God, and Jesus Christ is God. There is no power in the entire universe save what God delegates. The slain Lamb did not acquire this power. Rather it belongs to Him inherently.