Please accept my humble obeisance. All glories to Srila Prabhupada
Vasudeva Datta in Gaura Lila was Prahlad Maharaj's incarnation and His prayers were:
SB 9.21.12 - Vasudeva Datta made a statement to Sri Caitanya Mahaprabhu, requesting the Lord to liberate all living entities in His presence. Vasudeva Datta submitted that if they were unfit to be liberated, he himself would take all their sinful reactions and suffer personally so that the Lord might deliver them. A Vaisnava is therefore described as being para-duhkha-duhkhi, very much aggrieved by the sufferings of others. As such, a Vaisnava engages in activities for the real welfare of human society.
Adi 10.41 - Vasudeva Datta, the nineteenth branch of the Sri Caitanya tree, was a great personality and a most confidential devotee of the Lord. One could not describe his qualities even with thousands of mouths.
Vasudeva Datta, the brother of Mukunda Datta, was also a resident of Cattagrama. In the Caitanya-bhagavata it is said, yanra sthane krsna haya apane vikraya: Vasudeva Datta was such a powerful devotee that Krsna was purchased by him. Vasudeva Datta stayed at Srivasa Pandita's house, and in the Caitanya-bhagavata it is described that Lord Caitanya Mahaprabhu was so pleased with Vasudeva Datta and so affectionate toward him that He used to say, "I am only Vasudeva Datta's man. My body is only meant to please Vasudeva Datta, and he can sell Me anywhere." Thrice He vowed that this was a fact and that no one should disbelieve these statements. "All My dear devotees," He said, "I tell you the truth. My body is especially meant for Vasudeva Datta."
Vasudeva Datta was so kind to the living entities that he wanted to take all their sinful reactions so that they might be delivered by Sri Caitanya Mahaprabhu. This is described in the Fifteenth Chapter of the Caitanya-caritamrta's Madhya-lila, verses 159 through 180.