Srimad-Bhagavatam 7.9.38:
“My Lord, You, kill all the enemies of the world in Your multifarious incarnations in the families of men, animals, demigods, rsis, aquatics and so on. Thus You illuminate the worlds with transcendental knowledge. In the Age of Kali, O Mahapurusa, You, sometimes appear in a covered incarnation. Therefore, You, are known as Tri-yuga [one who appears in only three yugas].”
Adi Purana:
“O best of the brahmanas, My disguised form is eternal. In this way, with My own form hidden from ordinary sight I take the form of a devotee and appear among the people in general in order to establish and protect religious principles.”
Upa-purana:
‘O Brahmana, I occasionally take the sannyasa asrama in an attempt to bring the fallen people of Kali Yuga to take up the path of bhakti or devotional service to Lord Krishna.”
Kurma-Purana:
“The Supreme Person will appear in the first part of the age of Kali. He will appear in the home of a brahmana to save the embodied conditioned souls burning in the troubles of Kali-Yuga.”
Garuda-Purana:
“In the first part of the age of Kali, I will come among the brahmanas to save the fallen souls, who are being burned by the troubles of the age of Kali. I will take birth as the son of Saci, in Navadvipa-Mayapura. I will come in my complete spiritual form in the first part of Kali-Yuga. In the first part of Kali-Yuga, the Supreme Personality of Godhead will come in a gold-like form. First, He will become the husband of Laksmi (Srimati Laksmi Devi, Lord Caitanya’s first wife). Then He will become a sannyasi, near Lord Jagannatha who will appear in a divine wooden form.”
Nrsimha Purana:
“The Supreme Personality of Godhead who in the Satya-yuga appeared as a half-man, half-lion to cure a terrible disease that had ravaged the daityas, and who in the Treta-yuga appeared as a person named Rama (Lord Ramacandra), a person who defeated the ten- headed Demon Ravana, and who in the Dvapara-yuga removed the earth’s burden, and protected the Gopa (cowherd men) people of Vraja-pura, will appear again in the Kali-yuga. His form will be golden, He will delight in chanting the Lord’s holy names, and His name will be Caitanya.”