Because the vail was yet over their eyes so that they couldn't see. Everything was in murky shadow back then.
Seeing then that we have such hope, we use great plainness of speech: And not as Moses, which put a vail over his face, that the children of Israel could not stedfastly look to the end of that which is abolished: But their minds were blinded: for until this day remaineth the same vail untaken away in the reading of the old testament; which vail is done away in Christ. 2 Corinthians 3:12-14
If that was bothering you that I didn't answer, thank you for bringing it to my attention.