Baisakh (April–May) is a lunar month with a full moon.
This full moon is observed by Buddhists all around the globe as the anniversary of the Buddha's birth, enlightenment, and death.
The Buddha is revered by many Hindus as a wise and religious teacher, although he is not essential to Hinduism.
As a result, despite the fact that this full moon is still named after him, it is not a significant celebration.
The day of the full moon has lately been characterized as the greatest day of the year for bathing (snana) in holy rivers, a practice that the Buddha would have strongly condemned.
Given the auspiciousness associated with every full moon, it's possible that this is an attempt to "reclaim" the day as a Hindu festival by highlighting a uniquely Hindu ritual.
You may also want to read more about Hinduism here.
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