Lord Viṣṇu is called tri-yuga. He appears in three yugas — Satya, Tretā and Dvāpara — but in Kali-yuga He does not appear. From the prayers of Prahlāda Mahārāja, however, we understand that He appears garbed as a devotee in Kali-yuga. Lord Caitanya is that devotee. Kṛṣṇa appeared in the form of a devotee, but although He never disclosed Himself, Rūpa Gosvāmī could understand His identity, for the Lord cannot hide Himself from a pure devotee. Rūpa Gosvāmī detected Him when he offered his first obeisances to Lord Caitanya. He knew that Lord Caitanya was Kṛṣṇa Himself and therefore offered his obeisances with the following words: “I offer my respects to Kṛṣṇa, who has now appeared as Lord Caitanya.” This is also confirmed in the prayers of Prahlāda Mahārāja: in Kali-yuga He does not directly appear, but He appears as a devotee. Viṣṇu is therefore known as tri-yuga. Another explanation of tri-yuga is that He has three pairs of divine attributes, namely power and affluence, piety and renown, and wisdom and dispassion. According to Śrīdhara Svāmī, His three pairs of opulences are complete riches and complete strength, complete fame and complete beauty, and complete wisdom and complete renunciation. There are different interpretations of tri-yuga, but it is accepted by all learned scholars that tri-yuga means Viṣṇu. When Kardama Muni understood that his son, Kapila, was Viṣṇu Himself, he wanted to offer his obeisances. Therefore, when Kapila was alone he offered his respects and expressed his mind as follows.