antaryāmī, bhakta-śreṣṭha,--ei dui rūpa
śikṣā-guruke-the spiritual master who instructs; ta'-indeed; jāni-I know; kṛṣṇera-of Kṛṣṇa; sva-rūpa-the direct representative; antaryāmī-the indwelling Supersoul; bhakta-śreṣṭha-the best devotee; ei-these; dui-two; rūpa-forms.
One should know the instructing spiritual master to be the Personality of Kṛṣṇa. Lord Kṛṣṇa manifests Himself as the Supersoul and as the greatest devotee of the Lord.
Śrīla Kṛṣṇadāsa Kavirāja Gosvāmī states that the instructing spiritual master is a bona fide representative of Śrī Kṛṣṇa. Śrī Kṛṣṇa Himself teaches us as the instructing spiritual master from within and without. From within He teaches as Paramātmā, our constant companion, and from without He teaches from the Bhagavad-gītā as the instructing spiritual master. There are two kinds of instructing spiritual masters. One is the liberated person fully absorbed in meditation in devotional service, and the other is he who invokes the disciple's spiritual consciousness by means of relevant instructions. Thus the instructions in the science of devotion are differentiated in terms of the objective and subjective ways of understanding. The ācārya in the true sense of the term, who is authorized to deliver Kṛṣṇa, enriches the disciple with full spiritual knowledge and thus awakens him to the activities of devotional service.