Idol worship in Hinduism
No, it is not true. There are plenty of references in the religious texts regarding worshiping God through idols and images.For example, in this chapter of the Bhagavata Mahapuran Shri Krishna speaks about idol worship in brief:
The Deity form of the Lord is said to appear in eight varieties — stone, wood, metal, earth, paint, sand, the mind or jewels. [SB - 11.27.12]
Not just that, other puranas like Garuda, Agni, etc. talk about process of establishing idols, way of worshiping them and so on. But the scriptures that talk about the process of idol worship, temples, etc. in detail are the Pancharatras. In the vedas it is mentioned that vedas and puranas first originated from the Lord making the puranas the earliest reference containing idol worship. Otherwise, the Pancharatra texts are the earliest ones to talk about idol worship in detail.
As Shri Kirshna says in the above mentioned chapter, the Lord can be worshiped in three ways, Vedic, Tantric and a mixture of both. During ancient times like Satya and Tretaya people were mentally and spiritually advanced, so they were able to perform yajnas perfectly without needing to resort to idol worships. But as time passed people became more and more mentally and spiritually declined. Hence, properly following the scriptural injunctions of the Vedas became difficult and the practice of idol worship increased.
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