I imagine plenty of people noticed how Captain America’s shield made cameo appearances in the two “Iron Man” movies. For those who didn’t catch it, but have now seen “Captain America” and “The Avengers”, I bet the shield stands out the next time they see the Iron Man movies.
Things like that are called “easter eggs”, so named because they are hidden from plain sight (i.e. not an obviously essential plot element and most often blended into the background). They might have an overt part to play (as the shield does in Iron Man 2), but their greater significance is passed over by the uninitiated, only to be picked up on later when the person comes back to it a little more observant.
It seems to me that, in a manner of speaking, God left “easter eggs” in the Bible. That is, just like the shield in “Iron Man 1&2” points forward towards the person and work of Captain America, so too does the Old Testament point forward towards the person and work of Jesus Christ. (think of Jesus’ words in John 5:39, or his conversation with the disciples on the road to Emmaus in Luke 24)
Many examples could be offered, but let me suffice to name but 3.
1) The Protoevangelium (First Gospel) in Genesis 3:15, promising that the seed of the woman will bruise the Serpent’s head and be bruised himself in the process
2) The appearance of Melchizedek in Genesis 14:18-20, foreshadowing the Trifold office of the Christ as Prophet, Priest, and King
3) The brutal actions described in Psalm 22, detailing just how it would be that this Christ would be put to death, yet also delivered unto vindication
The list is potentially endless.
Call it easter eggs or whatever suits you, but it has well been said that Christ is on every page of the Scriptures. May we in our lifetimes learn to see this more every day!