And I beheld, and, lo, in the midst of the throne and of the four beasts, and in the midst of the elders, stood a Lamb as it had been slain, having seven horns and seven eyes, which are the seven Spirits of God sent forth into all the earth. (Revelation 5:6)

And I beheld, and, lo, in the midst of the throne and of the four beasts, and in the midst of the elders, stood a Lamb as it had been slain, having twelvehorns and twelve eyes, which are the twelve servants of God, sent forth into all the earth.

The number twelve used for the horns and eyes of the Lamb makes us think immediately of the twelve apostles.  It also reinforces they are servants of God, not multiple Holy Ghosts.

The fact they are represented as being a part of the Lamb (horns and eyes) shows us how close to Christ they are, how dependent on Him they are, how close to his thoughts and purposes they are.  It also gives us a sense of how indispensible the office of apostle is to the organization of the church. 

Horns are sharp and pokey and they are used in the scriptures as symbols of power.  Any time the apostles share their witness, they are being used as a power for the Lord.  (Prod, prod)

It is also interesting this verse tells us the Lamb is standing (and presumably alive), but as it had been slain, with wounds testifying to its death.  This represents the resurrected Christ, not the pre-crucifixion Christ.  I don’t know exactly what to say about this, but it fascinates me.  Maybe it is because the wounds are visible, so they can be witnessed by others, but they are no longer a source of trauma to the Lamb.  He overcame it all for us.   This isn’t a zombie Lamb; it’s a resurrected Lamb.  Death has no more power.