If Vaishnavism is so popular and wide spread in India, the credit must go to Sri Ramanuja, who took advantage of the ecstatic outpouring of the south Indian mystics, the Alvars, and produced a highly logical philosophy of knowledge soaked in devotion as the easiest means of God-realization.
There is only one sin. That is weakness.... The only saint is that soul that never weakens, faces everything, and determines to die game.
-Swami Vivekananda