I find Bahá’u'lláh’s use of sun imagery in his writings intriguing. In the Kitab-i-Iqan Bahá’u'lláh elucidates solar symbolism in scripture and describes the spiritual teachers of humankind as the ‘Suns of Truth’-
And now, concerning His words–”The sun shall be darkened, and the moon shall not give light, and the stars shall fall from heaven.” By the terms “sun” and “moon,” mentioned in the writings of the Prophets of God, is not meant solely the sun and moon of the visible universe. Nay rather, manifold are the meanings they have intended for these terms. In every instance they have attached to them a particular significance. Thus, by the “sun” in one sense is meant those Suns of Truth Who rise from the dayspring of ancient glory, and fill the world with a liberal effusion of grace from on high. These Suns of Truth are the universal Manifestations of God in the worlds of His attributes and names.
The Reality of Divinity may be compared to the sun, which from the height of its magnificence shines upon all the horizons; and each horizon, and each soul, receives a share of its radiance. If this light and these rays did not exist, beings would not exist; all beings express something and partake of some ray and portion of this light. The splendours of the perfections, bounties and attributes of God shine forth and radiate from the reality of the Perfect Man—that is to say, the Unique One, the supreme Manifestation of God. Other beings receive only one ray, but the supreme Manifestation is the mirror for this Sun, which appears and becomes manifest in it, with all its perfections, attributes, signs and wonders.
(Interestingly the rays of the sun or a reflection in a mirror were originally the metaphors used by Neo-Platonists such as Plotinus to describe the way the universe emanates from a transcendent God (the One) who remains unaffected or undiminished by creation).
The sun is also used as a metaphorical description of the attributes of God- for example in ‘Prayers and Meditations’ Baha’u'llah refers to-
‘the sun of Thine essence’
‘the splendours of the sun of Thy beauty’
‘the splendours of the Sun of Thy oneness’
In addition the sun serves as a metaphor for spiritual truth and understanding- for example-
This is the Sun that shineth in the heaven of Thy will and the splendor of which the veils of the workers of iniquity and the doubts of the evil doers can never cloud. …
Hold Thou the hand of this seeker who hath set his face towards Thee, O my Lord, and draw him out of the depths of his vain imaginations, that the light of certainty may shine brightly above the horizon of his heart in the days whereon the sun of the knowledge of Thy creatures hath been darkened through the shining of the Day-Star of Thy glory…
One of my favourite occurances of sun imagery is in ‘The Hidden Words’ when it is used to symbolise spiritual awakening-
O SON OF MAN! Many a day hath passed over thee whilst thou hast busied thyself with thy fancies and idle imaginings. How long art thou to slumber on thy bed? Lift up thy head from slumber, for the Sun hath risen to the zenith, haply it may shine upon thee with the light of beauty.