The foremost of all the Vaisnavas who reside at Navadvip is Sri Advaita Acarya, whose virtuous presence has made all the worlds blessed. He is the most preminent preceptor in all fields including knowledge, renunciation and devotion. In explaining Krsna-bhakti he is like Lord Sankara himself and whatever scriptures that exist within the three worlds, He explains them in the light of Krsna-bhakti.
With the intense eagerness he continually worshiped Sri Krsna with Tulasi manjaris and Ganges water. By the momentum of his spiritual force, his loud shouts pierced the coverings of this universe and resounding throughout Vaikuntha, reach the ears of Sri Krsna. Hearing this loving summons saturated with devotion, Sri Krsna advented Himself as Lord Chaitanya Mahaprabhu.
On the seventh day of the bright fortnight of the month of Magh, the great ocean of ecstasy swelled to its limits, being forcibly attracted by the moon of Advaita, who appeared from the womb of Sri Nabhadevi as the moon appears in the autumn sky. His father, Sri Kuvera Pandit floated in that ocean of joy. In great happiness he gave many gifts in charity to the brahmanas. Advaita Acarya is the combined incarnation of Maha Visnu and Sadasiva (who resides in Goloka). His two consorts, Sita and Sri are manifestations of Yoga Maya.
It is said that if Advaita Acharya is kind to a person, naturally Lord Chaitanya and Nityananda will also be kind to that person. Hence, unless one receives the mercy of Sri Advaita Acharya, one cannot avail of the mercy of Lord Chaitanya and Lord Nityananda.