As I read the Four Valleys, it gives me the impression that, like the Seven Valleys seems to do, it depicts a series of relationships that believers develop with the Manifestation of God. In particular it reminds me of this Hidden Word:
O Son of Man! Write all that We have revealed unto thee with the ink of light upon the tablet of thy spirit. Should this not be in thy power, then make thine ink of the essence of thy heart. If this thou canst not do, then write with that crimson ink that hath been shed in My path. Sweeter indeed is this to Me than all else, that its light may endure for ever.
Each Valley seems to describe a different degree of sacrifice. In the first Valley, the believer sacrifies himself: his substance, energy, effort, even his life. In the second Valley, the believer sacrifies his mind: thoughts, opinions, notions of Truth. In the third Valley, he sacrifices his heart: all that he cares for, every hope and goal now culminates in the Beauty of God. And in the fourth Valley he sacrifices his very self, until nothing else remains but consciousness of the Friend.