Srila Bhaktivinoda Thakura:

In the teachings of Sriman Mahaprabhu, there are two principal instructions: developing a taste for the chanting of the Lord’s holy names and displaying compassion for the fallen souls. The greatness of a Vaishnava depends on the extent to which he possesses these qualities… All good qualities of a Vaishnava automatically manifest in a Vaishnava who endeavors for these two qualities.

Sri Chaitanya-shikshamrita 1.7