The image of the Messiah was revealed to different prophets in different ways. This happened not because one of them was right...
The image of the Messiah was revealed to different prophets in different ways. This happened not because one of them was right and another mistaken, but simply because the person of the Messiah was too immense to be grasped in one glance centuries before His coming into the world. This greatness of Christ's person was the reason that He was often revealed to the preexilic prophets as a ruler or high priest: someone like Him could not possibly be an ordinary man.
Yet in these prophecies there was also a revelation of the Kingdom: after all, the Messiah truly is King, only He brought His Kingdom with Him, and it is not arranged according to the laws of the old world. But this is exactly what is hardest for us to imagine, because we know no kingdoms other than those we see on earth. The prophets did not know them either, and therefore the messianic Kingdom often appeared to them in the form of an earthly state (although almost always there was, in this seemingly quite earthly state, something not entirely earthly, something that could not exist without God's direct participation).
And it was to the Babylonian Isaiah that it was first revealed that the Messiah's greatness is not at all like the greatness of an earthly king. By earthly standards there is no greatness in Him. It is no accident that Isaiah calls the Messiah by a Hebrew word that can be translated both as "boy" or "adolescent" and as "slave": in Hebrew society slavery was always patriarchal; slaves lived in the household practically as younger family members, possessing no rights but not being deprived of shelter or food.
Christ, of course, was not a slave, but the point of the prophecy was not to indicate His social position, but to let everyone understand that the Messiah's ministry is not determined by His social position. His Kingdom is not of this world, and to be King He needs neither an army nor a state apparatus. He remains the Messiah while being, from the point of view of this world, no one, and the success of His messianic ministry is in no way connected with victory or defeat in this world. Against the background of messianic expectations that assumed the appearance of the Messiah as an earthly king, the prophecy of the Babylonian Isaiah proved highly relevant. Unfortunately, by the time of Christ's coming it had, if not been forgotten, then not been taken seriously or understood literally. But that is another story.