Definition - What does Vaishnavism mean?
Vaishnavism is the largest branch of modern Hinduism. Its devotees worship Vishnu, or one of his avatars, as the Supreme God. Vaishnavism has numerous sects and their beliefs vary.
Despite the differences, all Vaishnavas believe that there is one Supreme God over all creation. And like other Hindu branches, they believe in the existence of many lower deities under that Supreme God. Vaishnava beliefs are, in large part, based on the Upanishads, as well as the texts of the Vedas and the Bhagavad Gita, among others.
Vaishnavism is associated with Bhakti yoga, a spiritual yogic practice focused on love and devotion toward the Supreme God.
Yogapedia explains Vaishnavism
Also called Vishnuism, this form of Hinduism believes that Vishnu is the manifestation of brahman (supreme existence or absolute reality). Through his various incarnations – the most prominent of which are Krishna and Rama – Vishnu defends dharma (universal truth or moral law).
The various sects and groups within Vaishnavism differ in their worship of Vishnu. For some, the goal of bhakti (religious devotion) is moksha (liberation from the life-death cycle, or samsara). For others, the goal is prosperity and health.
Most Vaishnavas believe in the concept of a life of eternity with Vishnu after death. Some sects believe that the phenomenal world is not real. Others believe that Vishnu and the soul are separate entities. But one group, the Gaudiya sect, asserts that the relationship between Vishnu and the world is completely beyond comprehension.
Vaishnavas' beliefs in the concepts of bhakti and Bhakti yoga are founded largely on the sacred writings in the Upanishads. Bhakti yoga requires practicing devotion to the Supreme deity that's based on a sincere desire to please, rather than the hope of reward or the fear of punishment. This form of yoga is a path to spiritual liberation, or oneness with Vishnu.