To perform devotional service means to follow in the footsteps of Radharani, and devotees in Vrindavana put themselves under the care of Radharani in order to achieve perfection in their devotional service. In other words, devotional service is not an activity of the material world; it is directly under the control of Radharani. In Bhagavad-gita it is confirmed that the mahatmas, or great souls, are under the protection of the daivi prakriti, the internal energy—Radharani. So, being directly under the control of the internal potency of Krishna, devotional service attracts even Krishna Himself.


[Nectar of Devotion, Chapter 1]