Om Namo Bhagavate Vāsudevāya

Om Namo Bhagavate Vāsudevāya (ॐ नमो भगवते वासुदेवाय; ) is one of the most popular mantras in Hinduism and, according to the Bhagavata tradition, the most important mantra in Vaishnavism. It is called the Dvadasakshari Mantra, or simply Dvadasakshari, meaning the "twelve-syllable" mantra, dedicated to Vishnu or Krishna.

Origin
Bhagavatism, one of the traditions that was assimilated with what would become Vaishnavism, revered the Vrishni heroes, primary among them being Vāsudeva (Krishna). It may be concluded that the mantra was first associated with the reverence of Vāsudeva as the supreme deity before he was syncretised with Vishnu, after which it became an invocation of both deities.

Meaning
Om Namo Bhagavate Vasudevaya means "Om, I bow to Lord Vāsudeva or Lord Vishnu".

Details
Om Namo Bhagavate Vāsudevaya means "prostration to Vasudeva", who is variously understood as Krishna. The Vaishnava Upanishads state that this mantra is described on the Sudarshana Chakra: "Similarly, in the twelve petals, is placed the Vasudevan (the twelve-syllabled Mantra, Om Namo Bhagavate Vasudevaya)." The Sharada Tilaka, a Tantric text, states: "Dvadasharno mahamantrah pradhano Vaishnavagame"— The twelve lettered mantra is the chief among vaishnava mantras.

Similarly, this is referred to as the ultimate mantra in the Shrimad Bhagavatam. This twelve syllable mantra is known as a mukti (liberation) mantra, and a spiritual formula for attaining freedom. The mantra can also be found in the Vishnu Purana.

In the epic Mahabharata, Dhruva chanted this mantra in his penance as ordered by sage Narada.

In popular culture

 * Swami Vivekananda used this phrase multiple times in his lectures and letters.
 * Swami Sivananda suggested to repeat mantras like Om or "Om Namo Bhagavate Vasudevaya".
 * Vedanta philosopher Dayananda Saraswati wrote a book named "Om Namo Bhagavate Vasudevaya".
 * Willow Smith and Jahnavi Harrison put this mantra into their song Gajendra from their collaborative album RISE