The speaker is tied to a maple tree in a desert, sinking into rising sand and slowly breaking down. The leaves cut his face, the sun seems to mock him, and he is so thirsty he tries to drink his own sweat. Early on he asks, "what have I done to her," which suggests guilt. The poem seems to imagine this punishment as being tied to something he caused in a relationship, though it never says exactly what.
Then a woman appears, gentle and almost unreal, "a queen dressed in sparkling water." Her kiss fills him with water, the rope breaks, and the sand lets him go. The mood shifts from dread and exhaustion to relief and wonder. The repeated "again" builds a sense of rebirth, and the last word, "Found," answers the first, "Lost." Read this way, the desert is his remorse and isolation, and the woman's forgiveness is what brings him back to life.