Trivikrama: Because Kṛṣṇa's representative is nondifferent, he's a transparent medium, therefore if you surrender to him, then that's the same as surrendering to Kṛṣṇa. He so kindly sends His pure devotee for an opportunity. You can't say: "Well, where is God? I don't know how to surrender." He's sending His representative.
Prabhupāda: Kṛṣṇa's representative means the representative says the same thing as Kṛṣṇa says. Kṛṣṇa says: "Surrender unto Me," and the representative says: "Surrender to Kṛṣṇa." And because he delivers the real knowledge, he's as good as Kṛṣṇa. Therefore sākṣād-dharitvena samasta-śāstrair uktas tathā bhāvyata eva sadbhiḥ. The spiritual master may appear to be just like a common man, but he is to be respected as God, because he delivers the real message of God. That is the qualification of spiritual master. He does not manufacture anything. That is very easy. If I carry your message and educate people in that way, then there is no difficulty for me. Everything is there. Why shall I go to manufacture something imperfect? The perfect thing is already there. Simply I have to carry. A post peon—the money order is there; he has to simply carry and deliver to the person. And if he gets at time of need, he thanks the peon, "Oh, you have saved my life." It is like that. The message is already there. You have to simply deliver to the suffering humanity. Then he'll be relieved. And because he delivers the real reality, therefore he's worshiped as God. Sākṣād-dharitvena samasta-śāstrair uktas tathā bhāvyata eva sadbhiḥ. Ācāryaṁ māṁ hi vijānīyāt. Kṛṣṇa also says ācārya is . . . "I am ācārya." Because when there is, na ca tasmān manuṣyeṣu kaścin me priya-kṛttamaḥ (BG 18.69).