Kommentar zu Schir haSchirim 4:15

You are a garden spring. All this refers back to, “Your arid fields,” and he praises them like a fountain which irrigates them. The allegory is: It refers to the immersions of purification which the daughters of Yisroel immerse themselves.

And flowing streams from Levanon. From a place of cleanliness, without the murkiness of mud.