Why did the Lamb of verse 6 not step forward at this point?
Revelation 5:3 (ESV)
3And no one in heaven or on earth or under the earthwas able to open the scroll or to look into it,
The attitude that characterized the Lord Jesus Christ on earth is evident here too. He came to serve, not to draw attention to himself. In Revelation 5:1–14, too, he remained as it were in the shadows till the mighty angel pointed to him.
3 And no one in heaven or on earth or under the earth was able to open the scroll or to look into it,