The OED attests to several verb meanings of alight that have fallen out of common usage (marked rare):
trans. To shed light on; to illuminate, enlighten (lit. and fig.).
1999 D. Tobin Passage to Center 301: Such repose alights the face of The Tollund Man and Gunnar.
trans. To set light to; to light, ignite. Also fig.
2009 S. Akhter Faith & Philos. Islam vi. 89: The Holy Quran is an extraordinary pearl... Every fruit of good luck is found in it and every torch is alighted from it.
I would not use them in modern communication except for deliberate literary effect.
The etymology of this verb use of alight is treated as uncertain, but it may be a reduction of the obsolete onlight, which also means to shed light upon or to cause to shine. The OED further suggests that the adjective/adverb use of alight derived from the verb and was later reinterpreted by analogy to afire and aflame.