Genesis 3:24 (ESV)

24 He drove out the man, and at the east of the garden of Eden he placed the cherubim and a flaming sword that turned every way to guard the way to the tree of life.

The sending away was neither a request nor even just a command from the Lord. It was an action in which he was very actively involved. The words “drove out” in this verse clearly shows this. Man has to move out of Paradise and may not return to it. This is his punishment, yet also a rich protection. It is a condition for his salvation. The Lord places cherubim at the entrance to Paradise. This makes it clear that you could not enter Paradise in any other place. These cherubim, these angels, are not there for only a few days. No, they continued to remain there as guards. They have to keep every person out of Paradise with a flaming sword. This sword indicates God’s presence and especially the power of his judgment. He uses this judgment for the redemption of his people (see also Exodus 19:18; Psalm 104:4).