Ardent bhakti cannot rest satisfied with silent meditation and upāsanā especially when it overflows and expresses itself in the form of tears, tremors and trance and as bridal mysticism. Vedic offerings to gods are reinterpreted as Vedāntic offerings to Brahman. Brahman is beyond space and time and is formless. But He has a formless form of His own to respond to the needs of the worshippers and their prayers and praise. Though bhakti is for bhakti’s sake, the worshippers often pray for earthly and celestial boons and Bhagavān, as Providence, answers -their prayers. Contemplation on the inner self is supremely desirable but it is not what is actually possible for the average man of common sense. He wants something concrete to fix his mind upon. In His infinite mercy and love, God descends into humanity as arca or idol. Arca is not metal or stone symbol but is the permanent incarnation of God and the concretion of His krpā. In arca God is easily accessible to all at any time or in any place. God-hunger for man is more than man's hunger for God and as arca, He longs for communion with the devotee whom He regards as His very ātman or self. Bhakti and worship or pūja are the inner and the outer expressions of man's love of God. In His infinite love, He comes down and the mystic ascends to Him by Karma Yoga, Jñāna Yoga and Bhakti Yoga. Arca is the most accessible form of God for expressing our love through pūja or worship.

Worship can be offered in a variety of ways. We can worship Him by inner meditation or dhyāna. We can again worship Him by offering: flowers, incense, food and drink. We can also worship Him by simply uttering His names. The first method is difficult to practise as it implies the turning of the vision inward. The second is easy and lies within the reach of all people. The third is the easiest and the most efficacious of all. The worship of the idol or arca is really the worship of the living all-pervading presence of the Lord. The Deity responds to our bhakti and out of His grace, reveals His nature in and as arca. While avatāras are historic incarnations of God that come and go, arca is the permanent incarnation of God and He is ever accessible to the mystic. God comes to stay in the idol out of His grace and by virtue of our devotion and prayer.

There are two primary methods in the worship of God as Nārāyaṇa, namely, the Pāñcarātra and the Vaikhānasa. The Pāñcarātra Āgama is the word of Nārāryaṇa Himself and it is a sāttvika religion based on the practice of love. The Vaikhānasa is also of divine origin. The Śaiva Āgamās are traced to Siva. The Āgamas, therefore, claim the same validity as the Itihāsas and the Purāṇas.

Worship of God as arca or image is of two kinds, namely, temple and domestic worship. The former is meant for all and has continuity. It is conducive to the good of the commiinity as a whole. Domestic worship is, however, confined to the householder and his family. Again, there will be homa, bali and utsava in temple worship which are absent in domestic worship. Further there will be multiple images in temple worship.

The Āgamas refer to 96 varieties of temples of which 18 are prescribed for Viṣṇu and the remaining types are meant for other Gods. The essential parts of a temple are the garbhagṛiha or the sanctum sanctorum, the mukha maṇṭapa or the pavilion in front and the prākāra or the walls surrounding the sanctum for going round it or pradakṣiṇa. The garbhagṛha is surmounted by a vimāna or tower and the prākāra is provided with a gate or gopura. The prākāras may vary from one to seven according to the grandeur of the temple.

Five kinds of images are prescribed for temple worship of which dhruva the static aspect, and utsava, the dynamic aspect, are the most important. The images are of three types, the sthanaka or the standing posture, the āsana or the sitting posture and the sayana or the lying down posture. Each of these kinds may be of the yoga or the serene type, the bhoga or the blissful and the vira or the heroic.

The Āgamas furnish detailed instructions regarding the planning and construction of temples as regards position, size and the measurements of the vimāna and other parts of the temple. Just as the body is a living temple of God and the heart is His shrine, so the town is modelled on a spiritual plan with the temple at the centre. In addition to the temple to the ādimurti or the chief God there may be temples for the other incarnations of God, the Ālvārs, Nāyanmārs and the Ācāryas. The whole temple is pervaded by a religious atmosphere in which work is elevated into worship and worship is raised to the philosophical and spiritual level.

The festivals conducted in a temple are for the benefit of the community as a whole and they are of two kinds, the periodic and the occasional. While the devotee seeks the mūlavar or the God within, the utsavar, as the giver of grace, seeks the devotees outside and bestows His blessings on them. In addition to the periodic festivals like those at the time of the full moon or the equinoxes, festivals may be performed at any time out of devotion or desire to ward off evils in times of drought or cosmic calamities. The duration of the festivals may vary from one to 15 or 30 days. A flag is hoisted in the temple to indicate the course of the festival; and it is lowered at the end of the same. Once the flag is hoisted, none may leave the town until it is lowered. This indicates that the festival is for the benefit of the people. It is laid down that devotional festivals should be performed in the afternoon.

Great care is taken for maintaining the purity or sanctity of the temple. God is pure and perfect. Expiatory ceremonies are prescribed for the slightest act of impurity. The underlying idea is that God who is essentially pure and free from all kinds of taints, withdraws His presence from places polluted in the slightest degree as unfit for His stay. The devotee should go into it with pure body and mind. Cleanliness leads to godliness and only the pure in heart can reach God. Certain ceremonies are performed to purify the atmosphere of the temple if it is made impure. Expiatory ceremonies are prescribed for the entry of impure persons and animals into the temple. Even the appearance of fungus and anthills inside the temple is considered to be a fit occasion for expiation. Expiatory ceremonies are also described for portents which forestall evil to the country.

Bharata Desa is the birthplace of universal religion and is the holy land of the avatāras, ṛṣis, Ālvārs, Nāyanmārs, Ācāryas and other seers of God. The birthplace of avatāras and godly men is called a kśetra or sacred place sanctified by their advent in the interests of spiritualising humanity. Mother India has infinite capacity to produce godly men and is therefore worshipped as perpetually young though she has given birth to a countless number of sages and saints through the ages. The Vedāntins seek Brahman as the supreme Deity or sat or as the cosmic Lord or Īśvara; the mystics seek Him as the indwelling Self but all religious people adore the avatāra, historical or permanent, in the kśetrās of which seven are said to be the chief. Ayodhya is the birthplace of Sri Rama; Mathurā, Gokula and Bṛndavana are associated with the lila of Sri Kṛṣṇa. Kāsi is the heart of spiritual India. Kāsi is held sacred as the chief salvation giving city of India.

Arca is worshipped in five forms of which the most important is svayamvyakta like Tirupati.

The Lord in His infinite mercy incarnates here and is the very embodiment of redemptive love for all Jīvas. He summons all Jīvas from the hill-top to seek His feet and attain His grace. Other kṣetras are Śrīrangam, Puṣkaram, Melkote and Naimiśam. Kanci is a divyakṣetra to Varada consecrated by Brahma. Trivellore is an ārṣakṣetra consecrated by a ṛṣi. A mānusa kṣetra is established by a good man. Temples whose origin is not thus known are called purāna kṣetras and most temples come under this heading, Śaiva kṣetras also conform to type and Śiva dwells as the five elements, earth, water, fire, air and ether of which the most important is Chidambaram, permeated by cit. The pilgrim's progress, external but symbolical to the Vaiṣṇavites and the Śaivites, is from Badarināth and Kedāranāth in the north, to Kāsināth, Mathurānāth and Ayodhyanāth in the centre, to Pandarināth and Dwarakānāth in the west, to Jagannāth in the east and to Venkatanāth, Kāncināth, Ranganāth and Ramanāth in the south. The pilgrim then enters into the inner shrine and ascends to eternity.

Tirthas are tanks or rivers, the waters of which are considered to be holy on account of their association with some holy place or saint. Physical cleanliness is next to spiritual purity and godliness. Every kṣetra has a tirtha attached to it, a bath in which is said to cleanse our sins. Our Śrinivāsa kṣetra has in it Svāmipuṣkarini. All should bathe in it and purify themselves before approaching the presence of God. The Ganga is holy because it is said to have descended from Heaven and issued out of the feet of Viṣṇu. It was brought down by the severe penance of King Bhagiratha to remove the sins of the ten thousand sons of Sagara and send them to Heaven. The Godāvari and the Kāveri are equally sacred. Pilgrimages to holy places are symbolic of the pilgrimage of the soul to God. The end and aim of our life is the pilgrimage of the soul to God, the home of all eternal values like truth, goodness and beauty. Pilgrimages to kṣetrasenable the devotee to shed his prejudice due to the accidents of birth and station and long for His soul-sight. He attains vairāgya or the virtue of self-renouncement by minimising his wants and acquiring sāttvic endurance and patience. Contact with holy men fosters the spirit of human kinship and the kinship of souls leading to spiritual service. The great Ālvārs, Nāyanmārs and Ācāryas, therefore, took to pilgrimage from the Himālayas to the Setu to promote devotion in themselves and others.