There are degrees in seeing. For example, one sees a game of tennis, Federer vs Nadal make one brilliant rally after another. A savage, who, say does not have any understanding of sports, would think that two men went crazy and make some idiotic useless movements. But this savage also sees something. Now, an ancient Greek man, had he seen Federer vs Nadal play, would think that this is a certain strange and ugly sport, but he will understand that this is a sport, for he knows this category from his culture. However, he will not be able to know the rules, the full intrigue and the beauty of the game unless somebody from the world of tennis, some pundit of this sport, better, a tennis player himself, would explain him. Only then he can be said to see/know the sport of tennis and enjoy fully the brilliance of strikes and rallies.
Similarly here: the prophets knew only a portion of truth about God, and this is the meaning that they both have seen God and have not seen Him, for they saw God to the limit apportioned and permitted to them by God, but they could not reach full intimacy with Him, a full knowledge of Him. For instance, some of the prophets, could know that God punishes humans for their transgressions, and this knowledge is a certain "seeing" of God; however, Jesus who fully knows God, gave a new dimension to this knowledge: to wit, that even in the punishment is revealed not hatred, but love of God, who is all-loving and is merciful to both good and evil (cf. Matthew 5:45).
Therefore, all of the prophets, even the highest of them, is less blessed than the least of Jesus' disciples, for the prophets only dreamt about and remotely wished what the disciples actually see and perceive, i.e. the Incarnate God, Jesus (Matthew 13:17).
Now, only Jesus, being God knows God the Father completely and perfectly, as He Himself is known by the Father (John 10:15), equality of reciprocal knowledge between the Father and the Son necessarily implies the equality of their divine dignity as well, for what They know, they have, and if Father knows fully the Son and vice versa, then all their divine features are fully possessed by Both, thus Both being worship-able by the believers, because we worship God for His uncreated divine features, and those uncreated divine features are equally, fully and eternally possessed by both Father and the Son, thus it is impossible to worship God without worshiping Both.
Since 100% God became 100% man in the Person of Logos, Jesus Christ, then new dimension of intimacy between God and men was opened henceforth, which intimacy was not achieved even by the greatest of God-seeing prophets, Moses or Daniel etc., for their seeing was only limited, but now since God is already also human, humans have an incomparably greater closeness to God, so as to even have authority of becoming "children of God" (John 1:18).