Abraham Was a Christian
This idea bothers some folks, even many Christians, but the Bible says it... "...Abraham rejoiced to see my day," Jesus said (Jn 8:56). You know what else? Isaiah was too! "Isaiah...saw His glory, and spoke of Him" (Jn 12:41). And let's not leave out Moses. "...Moses...wrote of Me" (Jn 5:46). The point is simply that there is no disconnect between the Bible's Old and New testaments. No conflict, no contradiction. Luke 24:27 tells us Jesus taught his disciples about Himself beginning with the books Moses wrote, which would mean from Genesis through Deuteronomy.