Where the rules come from

Ritual rules were organised in the Kalpa Sūtras, one of the six Vedāṅgas (limbs of the Veda). These include the Śrauta Sūtras for large Vedic sacrifices, the Gṛhya Sūtras for household rites such as marriage and naming, and the Dharma Sūtras on conduct.

Later, the Smṛtis, Purāṇas and regional manuals (paddhatis) added the temple-style pūjā that most families know today. This is why practice differs by region, community and family — each follows its own paddhati, and all are valid within their tradition.

Kalpa Sūtras · Regional paddhatis

Karmakāṇḍa — the ritual way · Ask a Jyotishi your own question