What does 1 Corinthians 15:49 mean?

The Bible describes two states of existence in two separate bodies. One is the natural body that we're all familiar with. As was the case with Adam's body, these pre-death bodies are built to live on earth (Genesis 2:7). They are corrupted by sin and temporary. Those who are in Christ will receive a second body. This new body germinates, in a sense, from our old bodies (1 Corinthians 15:37). However, it is transformed in the moment of resurrection to follow the pattern of Christ's body instead of Adam's (1 John 3:2). That new body will be made of the same eternal material as Christ's body and built to last eternally with God in heaven.

Now, Paul adds that both bodies are marked by the image of the first of their kind. Every human being bears the image of Adam; our features, both external and internal, follow the pattern God established when forming Adam out of the earth. In a similar way, every Christian will in some way bear the image of the first one to be resurrected to a glorified body, Christ Himself. Since those bodies are eternal, we will bear His image forever.

Despite what some think, this is not intended to mean we will not be distinguishable as our unique selves in eternity. Bearing Christ's image does not mean that we will all wear Christ's specific face. Nor does it mean we will have the exact same, indistinguishable self. Here and now, we don't all look identical to Adam or to each other. Instead, we should understand that our glorified bodies will follow the pattern of Christ's body in the sense that we will share His defining characteristics (1 Corinthians 15:51).