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In Hindu temples we can see that many people does Dandvat Pranam.
Why it is consider as more important than normal namaskara mudra ?
So Krsna worship, mad-yaji, worshiping Krsna... Krsna says, "Worship Me." What is that? Mam namaskuru.
If you simply come in this temple and offer little obeisances, dandavat... Danda, danda means "rod"; vat means "like."
Just like one stick falls straight on the ground, similarly, if we fall straight before the Deity, that is called dandavat, "like the stick."
Dandavat-pranama. Prakrsta-rupena namrata. Namrata is required. Jnane prayasam udapasya namanta eva. Namanta. Be submissive. So this dandavat is the symbolic presentation of submission.
And Krsna wants that sarva-dharman parityajya mam ekam saranam vraja [Bg. 18.66], submission. The bhakti process is simply submission. So mad-yajino 'pi yanti mam [Bg. 9.25].
If you do not study or if you have no education to study Vedic literatures, you simply... The temple is installed for this purpose, that if somebody comes, simply offers his obeisances before the Deity, before the spiritual master, simply by doing that, he will become perfect.