Why is Gaṇeśa worshipped first?

he is the Lord of beginnings and the remover of obstacles, so every good work starts by remembering him.

Gaṇeśa is called Vighneśvara, the Lord of obstacles, and Gaṇapati, the leader of Śiva’s hosts. Remembering him first is a way of asking that the work ahead go smoothly, and also of starting with humility and a clear mind. That is why weddings, housewarmings, exams, new shops and even the first page of a notebook (“Śrī Gaṇeśāya namaḥ”) begin with him.

In practice, even when the main pūjā is for Śiva, Devī or Viṣṇu, a small Gaṇeśa pūjā comes first: a short prayer, a flower, a little rice or a betel nut kept as Gaṇeśa if there is no idol. The Gaṇapati Atharvaśīrṣa calls him the one who is present before all.

You do not need anything elaborate. A folded-hand “Oṁ Gaṁ Gaṇapataye namaḥ” before you begin is a complete and sincere start.

Tradition says Śiva and Pārvatī once set their sons a race around the world. Kārttikeya set off on his peacock, while Gaṇeśa simply walked around his parents, saying they were his whole world. Pleased, they blessed him to be worshipped first.

Source: Gaṇapati Atharvaśīrṣa; Purāṇic tradition · Also called Vighneśvara, Vināyaka

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