Absolute knowledge consists of Brahman, Paramātmā and Bhagavān. This conclusion is not the same as that of the monists. Śrīla Advaita Ācārya was given the title of ācārya because He spread the bhakti cult, not the philosophy of monism. The true conclusion of advaita-siddhānta, expressed at the very beginning of the Caitanya-caritāmṛta (CC Adi 1.3), is not the same as the philosophy of the monists. Here advaita-siddhānta means advaya-jñāna, or oneness in variety. Actually Śrīla Nityānanda Prabhu was praising Śrīla Advaita Ācārya through friendly mock fighting. He was giving the Vaiṣṇava conclusion in terms of the Bhāgavatam's conclusive words, vadanti tat tattva-vidaḥ. This is also the conclusion of a mantra in the Chāndogya Upaniṣad, ekam evādvitīyam.
A devotee knows that there is oneness in diversity. The mantras of the śāstras do not support the monistic conclusions of the impersonalists, nor does Vaiṣṇava philosophy accept impersonalism without variety. Brahman is the greatest, He who includes everything, and that is oneness. As Kṛṣṇa says in the Bhagavad-gītā (7.7), mattaḥ parataraṁ nānyat: there is no one superior to Kṛṣṇa Himself. He is the original substance because every category emanates from Him. Thus He is simultaneously one with and different from all other categories. The Lord is always engaged in a variety of spiritual activities, but the monist cannot understand spiritual variety. The conclusion is that although the powerful and the power are one and the same, within the energy of the powerful there are varieties. In those varieties there is a distinction between the different parts of one's personal self, between types of the same category, and between types of different categories. In other words, there is always variety in the categories, which are understood as knowledge, the knower and the knowable. Due to the eternal existence of knowledge, the knower and the knowable, devotees everywhere know about the eternal existence of the form, name, qualities, pastimes and entourage of the Supreme Personality of Godhead. Devotees never agree with the monists' preaching of oneness. Unless one adheres to the conceptions of the knower, the knowable and knowledge, there is no possibility of understanding spiritual variety, nor can one taste the transcendental bliss of spiritual variety.