Why wouldn't the lover's heart be illuminated when the thought of the beloved has itself turned into a lamp?

Here, the poet creates a luminous picture of love's gentle power. The lover's heart, which could so easily sink into the dark corners of sorrow or longing, is instead flooded with warmth and radiance. The mere thought of the beloved acts like a lit lamp, reminding us that in true love, even absence cannot bring gloom—a simple memory is enough to brighten the entire soul.