King Bali, the mighty demon of the Vedic era, was an ardent devotee of Goddess Laxmi from whom he had obtained blessings of invincible protection (raksha kavach) in the form of a sacred rakhee.
The great sage, Maharishi Brihaspati, pointing at King Bali’s acquired strength, directed Shachi, the pious and spiritual wife of King Indra, to invoke on her spiritual strength and tie a rakhee on King Indra’s wrist, providing him with invincible protection in his fight against evil forces with the following blessings:
Yena baddho Bali Rajaa Daanavendro mahaabalah
Tena twam anubadhnaami, Rakshe maa chala maa chala.
(I am tying this rakhee on to you similar to the one that was tied to the powerful king of demons—Bali, oh Raksha! Be firm and do not waver.)
With this invincible protection given by Shachi,
King Indra overpowered the evil forces.
[This story is taken from the Raksha Bandhan card published by Hindu Swayamsevak Sangh (UK).]