Why do we worship Deities?
The Vedic tradition has mastered the sacred science of enlivening Divinity in the Deities, the rare process of turning the idol into a living Divinity having its own independent intelligence. By the ritual of Prana Pratistha, breathing life into matter, an Avatar invokes a unique Divine living presence into a Deity, called Archa Avatār - which radiates specific energies. Deities, thus, are the embodiments of Cosmic Consciousness. They are literally worshipped as a direct living presence of Divine. For the one, who has found the greatest wealth – Sadguru, the ultimate spiritual Guru, the embodiment of all Gods-Goddesses, sarva devadevi svarupa - in such a disciple, dawns the ultimate truth that – Guru is Shiva and Shiva is Guru.
Thus, for the initiated disciple, Sri Guru Pāduka, the sacred sandals of Sri Guru and Ātma Linga are the direct living presence of Sri Guru and Sadashiva. They listen and respond to our prayers, and through them we personally worship the whole Cosmos.
Sri Guru Puja and Sri Shiva Puja perform the puja.
"Practicing the presence of God leads you to Bhāva Samādhi directly. Practicing the presence of God means cognizing his presence is there with you and constantly relating with him, keeping him present in your presence." ~ THE SUPREME PONTIFF OF HINDUISM BHAGAWAN SRI NITHYANANDA PARAMASHIVAM