The procedure for worship of God in Vaishnavism is elaborate and the details are given in the Nityagrantha of Ramanuja based on the Pancharatra treatises. According to Vaishnava tradition, the method of Bhaga-vad aradhana or worshipping God is to be learnt from a qualified preceptor after the individual is duly initiated by the prescribed sacrament. This condition is imposed in order to maintain the sacred character of the mantras which are to be used in the mode of worship.

Requirements for worship of God
The first requirement is the maintenance of physical and mental purity of the worshipper for which certain preliminary purificatory acts are prescribed. The idol of God is to be approached with a feeling of devotion and a sense of fear towards the Holy.

Stages in Worship of God
There are six stages which mark the mode of worship. In the first stage known as mantrasana, the worshipper offers himself and all his belongings to God and seeks His blessings and permission to commence the worship. He offers to God arghya or water with a spoon or small vessel as a token of washing the hands of the deity, padya or water in the same manner to wash the feet and acamaniya or water in the same way for sipping as an internal purification. These are symbolic methods of receiving an elderly respected person and the same kind of respectful offerings are made to the deity too.

In the second stage known as snanasana, a holy bath is given to the idol with the recitation of the Pumsa sukta.

The third stage called alarhkarasana is intended to decorate the idol with clothes, flowers and ornaments. During this stage, the sandal paste (gandha), incense (dhupa) and dipa or waving of light either by burning a piece of camphor or cotton wick dipped in oil are offered. At this time arhcana or the offering of tulsi (basil) leaves and flowers is done with the recitation of Vedic mantras, the selected passages from the sacred works and the names of Vishnu, specially the names of twelve vyuha manifestations of Vishnu.

In the fourth stage named bhojyasana, offering in the form of cooked food is made to the idol.

In the next stage known as mantrasana God is presented with fruits and betel leaves and also camphor light. The Lord is also adored with the recitation of the concluding hymns of the Tiruppavai (a Tamil composition of Andal, one of the twelve Tamil saints) and the opening hymn of Periyalvar`s Thiruppallandu, which is a benediction for Lord`s glory to continue forever.

The sixth and the final stage which is called Paryankasana is intended to put back the idol to rest. After concluding the worship, the devotee is required to prostrate himself before God, circumambulate and with utter humility seek forgiveness of all the sins committed.

Worship of God at home
The mode of worship outlined above is what is generally prescribed for observance at home. The object of worship may be an idol of (some form of) Vishnu which is duly consecrated or it may just be a special stone in the shape of a round black pebble known as salagrama which is collected from the sacred river Gandak in Nepal. According to the Puranas, God is ever present in such stones. As they need no consecration, unlike the icons they are preferred for worship at the homes of Vaishnavas as a symbol of God. The worship of God at home is to be performed by all Vaishnavas irrespective of the caste including women. In the case of those who are not eligible to recite Vedic mantras, they can adopt non-Vedic or tantrik mantras.

Worship of God in the temples
The method of worship to be performed at the temples is somewhat different from what obtains at homes and are also very elaborate. Not all persons are permitted to do the puja at temples. In the case of the temples following the Vaikhanasa system, only those born in the family of the Vaikhanasa temple priests can do the puja. As regards the temples adopting the Pancharatra method, the temple priests have to get themselves qualified for worship by undergoing a formal initiation ceremony known as diksa. The daily worship of Vishnu at home is however an imperative for every devoted Vaishnava.

Thus, discussed above is the mode of worship of God as advocated by the Vaishnava religion.