Rev.21:3 mentions that the 'tent of God.' will be with mankind. Why a "tent"? Tents are typically associated with temporary conditions, whether it be camping or refugee situations or with nomadic peoples. Is God’s “residence” with mankind only temporary? Will he pull away from us?
No, that is not the mental imagery that is being painted for us in this passage. God himself resides in heaven and the earth is called his footstool. So God does not literally come down to reside on earth. It simply, according to scripture, could not contain him. (“But wait!,” you say, “verse 3 also plainly says that God will reside with them. That sounds like a contradiction to me.” Actually it is not. During the wilderness trek of the children of Israel (Jacob), God’s presence with and attentive protection for his people was indicated by other visible manifestations.) More than any other generation, ours can appreciate how this might be spoken of as if someone was “right there” with us. First, with the inventions of the telephone and television, people made exclamations that it felt “as if” that person were right there with them or that “It felt as if I were actually right there visiting the location.” Now, with the opportunity to use internet video communications, once again people are making expressions that are similar. (For me, I’ve personally been amazed with GoPro videos that did give a very near “real sensation” of an experience.) In a similar but not specifically detailed manner, God will reside with mankind. We will feel even more the full benefits of God’s good favor and care.
What then is the picture Revelation 21:3,4 is painting in our minds? Tents are also a protection from the elements. God’s spreading his tent over all mankind is intended to demonstrate not only his protection but his welcoming us into his universal united family. This protection will last forever as mentioned at Rev.21:4. More information is available here (see last two paragraphs).