Indeed, You diminished this burden formerly by incarnating in the form of a fish, a horse (Hayagriva), a tortoise, a lion (Lord Nrsimha), a boar (Lord Varaha) and a swan

Expressions researched:
"Indeed, You diminished this burden formerly by incarnating in the form of a fish, a horse [Hayagrīva], a tortoise, a lion [Lord Nṛsiṁha], a boar [Lord Varāha] and a swan"

Sri Caitanya-caritamrta

CC Madhya-lila

Indeed, You diminished this burden formerly by incarnating in the form of a fish, a horse [Hayagrīva], a tortoise, a lion [Lord Nṛsiṁha], a boar [Lord Varāha] and a swan. You also incarnated as Lord Rāmacandra, Paraśurāma and Vāmana, the dwarf. You have always protected us demigods and the universe in this way. Now please continue.

CC Madhya 20.299, Translation and Purport

“‘O Lord of the universe, best of the Yadu dynasty, we are offering our prayers unto You mainly to diminish the heavy burden of the universe. Indeed, You diminished this burden formerly by incarnating in the form of a fish, a horse [Hayagrīva], a tortoise, a lion [Lord Nṛsiṁha], a boar [Lord Varāha] and a swan. You also incarnated as Lord Rāmacandra, Paraśurāma and Vāmana, the dwarf. You have always protected us demigods and the universe in this way. Now please continue.’

This is a quotation from Śrīmad-Bhāgavatam (SB 10.2.40).