Question about John the Baptist’s proclamation of the Lamb of God ~ Why did Jesus’ apostles not know (or choose to forget) that Christ would be sacrificed for us?

John (Jesus’ cousin) is considered as the last Old Testament prophet. It was his purpose to prepare the way for the Messiah. He knew the sacrificial code and so when he called Jesus the Lamb of God he was prophesying about what would happen to Jesus – death through sacrifice.

My struggle is why the apostles didn’t remember this and instead formed their own ideas about who Christ would become. Do I do the same thing today? Do I really know Christ? Paul said, “…I consider everything a loss compared to the surpassing greatness of knowing Chris Jesus my Lord, for whose sake I have lost all things” in Philippians 3:8.