What does light symbolize in "The Lady of Shallot"?

In Alfred Lord Tennyson’s famous poem “The Lady of Shalott,” a fair maiden is trapped in a tower weaving, cursed if she ever stops her work to gaze out her window. Light bears symbolic significance in the poem. Let’s examine the first description of light that appears in order to understand what that light represents:

The sunbeam showers break and quiver
In the stream that runneth ever
By the island in the river
Flowing down to Camelot.

This description of the sunlight on the river that leads to Camelot indicates that the water surrounding the Lady’s tower isolates her from the outside world. The water itself “breaks” and makes “quiver” sunlight, which suggests that the light represents a connection with Camelot, or other people.
In parts 1 and 2, the speaker describes moonlight and what the Lady of Shallot is able to glimpse in her mirror during the nighttime. After making out the shape of two newlyweds, the Lady of Shallot remarks, “'I am half sick of shadows.’” This suggests that she feels isolated and trapped by the darkness that consumes her surroundings. This makes darkness the symbolic opposite of light.
The true significance of light, however, becomes clear when the Lady sees Lancelot for the first time:

The sun came dazzling thro' the leaves,
And flam'd upon the brazen greaves
Of bold Sir Lancelot.
. . . His broad clear brow in sunlight glow'd

Lancelot is literally swathed in sunlight, and the Lady of Shallot is so enamored of the knight’s beauty that she is compelled to turn away from her weaving and gaze upon him. If one considers that the Lady of Shallot is lonely, and that the shadows she is “half sick of” are happy lovers, the light in which Lancelot is bathed represents her desire for love. In addition, this desire is a temptation for the Lady of Shallot, who dies shortly after admiring the physical form of a man.
Overall, light in this poem represents desire, love, connection, and temptation.