Why did Lord Hanuman decide to spend his life as a celebate?
No, Hanuman was technically not a bachelor (Brahmachari). His wife was Suvarchala¹ who was the daughter of Surya (the Sun god). According to Surya, Suvarchala was an ayonija (born without [the participation] of the yoni).
Because he wanted to learn Nava Vyakarnas (the 9 Grammar Rules), he has to marry, and being an Aajanma Brahmachari (life-long bachelor), Hanuman was not eligible to study it. Surya grants him a boon that he will still be a bachelor even after marriage as a Prajapatya Brahmachari and will maintain his celibacy.
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