How Ancient is the Idea of Christ’s “Incarnation”?

Last week I was asked about the famous passage often known (among scholars) as the “Christ Hymn” of Philippians, 2:6-11. For a very long time (mid 20th c?) scholars have argued that it is a passage Paul did not write himself, but one that he is actually *quoting*. The passage seems to affirm the idea that Christ existed *before* he came into the world.

That may not seem weird to modern Christians, but in fact the only place where the idea is (otherwise) explicitly stated is in the Gospel of...