Now full in view the creature stood Now vanished in the depth of wood; Now luring with a languid flight, Now like a meteor lost to sight. With trembling limbs away he sped; Then like the moon with clouds o’erspread Gleamed for a moment bright between The trees, and was again unseen.

In plain words: The golden deer keeps teasing Rama. It shows itself clearly, then disappears into the woods, then flashes into view again between the trees like the moon peeking out from clouds.