These forms incarnate not only to give pleasure to the devotees but to reestablish devotional service and perform other activities which vitally concern the Supreme Personality of Godhead. Some of these forms are incarnations mentioned in the scriptures, such as the Viṣṇu incarnation, Trivikrama incarnation, Nṛsiṁha incarnation and Vāmana incarnation.
In the Siddhārtha-saṁhitā there is a description of the twenty-four forms of Viṣṇu, and these forms are named according to the position of the symbols in Their four hands. When describing the positions of objects in the hands of the Viṣṇu mūrtis, one should begin with the lower right hand and then move to the upper right hand, to the upper left hand and finally to the lower left hand. In this way, Vāsudeva is represented by club, conch shell, disc and lotus flower. Saṅkarṣaṇa is represented by club, conch shell, lotus flower and disc. Similarly, Pradyumna is represented by disc, conch shell, club and lotus flower.