Albert Barnes Commentary Revelation 6:7

"And when he opened the fourth seal, I heard the voice of the fourth living creature saying, Come." — Revelation 6:7 (ASV)

And when he had opened the fourth seal. (See Barnes on Revelation 5:1).

I heard the voice of the fourth beast say. The flying eagle. (See Barnes on Revelation 4:7).

As in the other cases, there does not appear to have been any particular reason why the fourth of the living creatures should have made this proclamation rather than either of the others. It was poetic and appropriate to represent each one in his turn as making proclamation.

Come and see. (See Barnes on Revelation 6:1).