The sankirtana movement inaugurated by Lord Caitanya is a transcendental pastime of the Lord. “By it I live simultaneously to preach and popularize this movement in the material world.” In that sankirtana movement of Lord Caitanya, Nityananda and Advaita are His expansions, and Gadadhara and Srivasa are His internal and marginal potencies. The living entities are also called marginal potency because they have, potentially, two attitudes-namely the tendency to surrender unto Krsna and the tendency to become independent of Him. Due to the propensity for material enjoyment, the living entity becomes contaminated by the material world. When a living entity is dominated by a desire for material enjoyment and becomes entangled in material life, he is subjected to the threefold miseries of material existence. He is just like a seed sown in the earth. If a seed is overpowered by too much water, there is no possibility of its fructifying. Similarly, if a man is captivated by material enjoyment, and even if the seed of such enjoyment is within the heart of the conditioned soul, he can be overpowered by a flood of transcendental activities performed in love of God. In this way his potential seed cannot fructify into a conditional life of material existence. The conditioned living entities in the material world, especially in the present Age of Kali, are overpowered by the flood of love of God inaugurated by Lord Caitanya and His associates.

Srila Prabhupada, TLC, Ch. 17