"My God, my God, why hast thou forsaken me? why art thou so far from helping me, and from the words of my roaring?"(Ps. 22:1)
When Jesus had been on the cross for six hours (according to Mark's account), he cried out "Eloi, eloi, lama sabachthani?", which is the first line in Psalm 22. In doing so, he was able to say much more to those who knew the psalms and had their hearts open to understanding than those who did not know the Psalms or had closed their minds to understanding were able to receive.
Does God sometimes give us the message on a day when we don't need it and the key to unlock it on the day when we do? When they sang together, what songs did Jesus and his disciples sing, and could they have imagined yet what the same words would later mean?