There are many learned sages, philosophers and transcendentalists who try to conquer the senses, but in spite of their endeavors, even the greatest of them sometimes fall victim to material sense enjoyment due to the agitated mind. Even Viśvāmitra, a great sage and perfect yogī, was misled by Menakā into sex enjoyment, although the yogī was endeavoring for sense control with severe types of penance and yoga practice. And, of course, there are so many similar instances in the history of the world. Therefore, it is very difficult to control the mind and senses without being fully Kṛṣṇa conscious. Without engaging the mind in Kṛṣṇa, one cannot cease such material engagements. A practical example is given by Śrī Yāmunācārya, a great saint and devotee, who says:
yad-avadhi mama cetaḥ kṛṣṇa-pādāravinde
nava-nava-rasa-dhāmany udyataṁ rantum āsīt
tad-avadhi bata nārī-saṅgame smaryamāne
bhavati mukha-vikāraḥ suṣṭhu niṣṭhīvanaṁ ca
"Since my mind has been engaged in the service of the lotus feet of Lord Kṛṣṇa, and I have been enjoying an ever new transcendental humor, whenever I think of sex life with a woman, my face at once turns from it, and I spit at the thought."
Kṛṣṇa consciousness is such a transcendentally nice thing that automatically material enjoyment becomes distasteful. It is as if a hungry man had satisfied his hunger by a sufficient quantity of nutritious eatables. Mahārāja Ambarīṣa also conquered a great yogī, Durvāsā Muni, simply because his mind was engaged in Kṛṣṇa consciousness (sa vai manaḥ kṛṣṇa-padāravindayor vacāṁsi vaikuṇṭha-guṇānuvarṇane).
(Bhagavad-Gita----2:60----purport).

Śrī Yāmunācārya Albandaru of South India said, "O my Lord! You are unknowable to persons involved with atheistic principles, despite Your uncommon qualities, features and activities, despite Your personality's being confirmed by all the revealed scriptures in the quality of goodness, and despite Your being acknowledged by the famous authorities renowned for their depth of knowledge in the transcendental science and situated in the godly qualities."
(Bhagavad-Gita----7:15----purport).

Those who are worshipers of demigods have been described as less intelligent persons, and here the impersonalists are similarly described. Lord Kṛṣṇa in His personal form is here speaking before Arjuna, and still, due to ignorance, impersonalists argue that the Supreme Lord ultimately has no form. Yāmunācārya, a great devotee of the Lord in the disciplic succession of Rāmānujācārya, has written two very appropriate verses in this connection. He says,
tvāṁ śīla-rūpa-caritaiḥ parama-prakṛṣṭaiḥ
sattvena sāttvikatayā prabalaiś ca śāstraiḥ
prakhyāta-daiva-paramārtha-vidāṁ mataiś ca
naivāsura-prakṛtayaḥ prabhavanti boddhum
"My dear Lord, devotees like Vyāsadeva and Nārada know You to be the Personality of Godhead. By understanding different Vedic literatures, one can come to know Your characteristics, Your form and Your activities, and one can thus understand that You are the Supreme Personality of Godhead. But those who are in the modes of passion and ignorance, the demons, the nondevotees, cannot understand You. They are unable to understand You. However expert such nondevotees may be in discussing Vedānta and the Upaniṣads and other Vedic literatures, it is not possible for them to understand the Personality of Godhead." (Stotra-ratna 12)
(Bhagavad-Gita----7:24----purport).

Instead of being attracted by material beauty, if one is accustomed to be attracted by the beauty of Rādhārāṇī and Kṛṣṇa, then the statement of Bhagavad-gītā, paraṁ dṛṣṭvā nivartate (B.G.9:59), holds true. When one is attracted by the transcendental beauty of Rādhā and Kṛṣṇa, he is no longer attracted by material feminine beauty. That is the special significance of Rādhā-Kṛṣṇa worship. That is testified to by Yāmunācārya. He says, "Since I have become attracted by the beauty of Rādhā and Kṛṣṇa, when there is attraction for a woman or a memory of sex life with a woman, I at once spit on it, and my face turns in disgust." When we are attracted by Madana-mohana and the beauty of Kṛṣṇa and His consorts, then the shackles of conditioned life, namely the beauty of a material woman, cannot attract us.
(Srimad bhagavatam----3:31:38----purport).

Śrīla Yāmunācārya has recited this verse in his Stotra-ratna (43):
bhavantam evānucaran nirantaraḥ
praśānta-niḥśeṣa-manorathāntaraḥ
kadāham aikāntika-nitya-kiṅkaraḥ
praharṣayiṣyāmi sanātha-jīvitam
"By serving You constantly, one is freed from all material desires and is completely pacified. When shall I engage as Your permanent eternal servant and always feel joyful to have such a fitting master?"
(Srimad bhagavatam----9:8:24----purport).

Śrī Yāmunācārya, in his prayers to the Lord, has expressed a similar idea in the following words: "My dear Lord, I may be living within some body as a human being or as a demigod, but whatever mode of life, I do not mind, because these bodies are simply by-products of the three modes of material nature, and I, who am in possession of these bodies, am surrendering myself unto You."
(Nectar of Devotion).

Śrī Yāmunācārya praises Kṛṣṇa's power of forgiveness with the following statement: "My dear Lord Rāmacandra, You are so merciful to have excused the crow's clawing on the nipples of Jānakī simply because of his bowing down before You." Once Indra, the King of heaven, assumed the form of a crow and attacked Sītā (Jānakī), Lord Rāmacandra's wife, by striking her on the breast. This was certainly an insult to the universal mother, Sītā, and Lord Rāmacandra was immediately prepared to kill the crow. But because later on the crow bowed down before the Lord, the Lord excused his offense. Śrī Yāmunācārya further says in his prayer that the forgiving power of Lord Kṛṣṇa is even greater than that of Lord Rāmacandra, because Śiśupāla was always in the habit of insulting Kṛṣṇa—not only in one lifetime, but continually throughout three lives. Still, Kṛṣṇa was so kind that He gave Śiśupāla the salvation of merging into His existence. From this we can understand that the goal of the monist to merge into the effulgence of the Supreme is not a very difficult problem. Persons like Śiśupāla who are consistently inimical to Kṛṣṇa can also get this liberation.
(Nectar of Devotion).