Whom do you consider the greatest religious guru India ever had ?
1. Adi Shankara.
2. Swami Ramakrishna Paramahansa
3. Chandrasekhara Saraswathi Swamigal.(affectionately called as Periyavar)
4. Swami Vivekanand.
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We are puny humans comapred to the hallowed names you have mentioned.
We are duffers when we even try to comapre or consider their greatness so I do not have the audacity to even think of it.
But I can say for myself and the impression some have left with their philosophy...religious achievements...and the revered Swami Vivekananda has left HIS mark on my soul.
With his realistic words and the courage with which he faced the usually
antagonistic and mentally closed western world culture of the 19th century and the relevance of his thoughts even for the common man.