The Sun

The sun symbolizes Stella's eyes, which the speaker pays close attention to as he attempts to "read" her facial expressions for signs of affection. Her eyes are also, the speaker argues, the thing that bring light into his dark day.

Stars

Like the sun, stars also symbolize Stella ("Stella" in Latin means "star") and the brightness that she brings into the speaker's otherwise melancholy life. He makes frequent reference to how "rare" a star she is, suggesting that he finds her different from all other stars - and therefore all other women - with which he is familiar.

Kings

Kings symbolize figures of power in the sequence, and are used to demonstrate the power dynamics between men and women and lovers more generally. A secondary reading may also suggest that Sidney's use of kings and kingship in the sequence is related to his political agenda...