The best way to compensate for one's sinful acts is to give up one's body at once, and Brahmā, the leader of the living entities, showed this by his personal example. Brahmā has a fabulous duration of life, but he was obliged to give up his body due to his grievous sin, even though he had merely contemplated it in his mind without having actually done it.

This is a lesson for the living entities, showing how sinful an act it is to indulge in unrestricted sex life. Even to think of abominable sex life is sinful, and to compensate for such acts, one has to give up his body. In other words, one's duration of life, blessings, opulence, etc., are decreased by sinful acts, and the most dangerous type of sinful act is unrestricted sex.

Ignorance is the cause of sinful life, or sinful life is the cause of gross ignorance. The feature of ignorance is darkness or fog. Darkness or fog still covers the whole universe, and the sun is the only counteracting principle. One who takes shelter of the Lord, the perpetual light, has no fear of being annihilated in the darkness of fog or ignorance.

(Srimad Bhagavatam--------3:12:33-------purport).

One should practice nonviolence and truthfulness, should avoid thieving and be satisfied with possessing as much as he needs for his maintenance. He should abstain from sex life, perform austerity, be clean, study the Vedas and worship the supreme form of the Supreme Personality of Godhead.
The word puruṣārcanam in this verse means worshiping the Supreme Personality of Godhead, especially the form of Lord Kṛṣṇa. In Bhagavad-gītā it is confirmed by Arjuna that Kṛṣṇa is the original puruṣa, or Personality of Godhead, puruṣaṁ śāśvatam. Therefore in yoga practice one not only must concentrate his mind on the person of Kṛṣṇa, but must also worship the form or Deity of Kṛṣṇa daily.

A brahmacārī practices celibacy, controlling his sex life. One cannot enjoy unrestricted sex life and practice yoga; this is rascaldom. So-called yogīs advertise that one can go on enjoying as one likes and simultaneously become a yogī, but this is totally unauthorized. It is very clearly explained here that one must observe celibacy. Brahmacaryam means that one leads his life simply in relationship with Brahman, or in full Kṛṣṇa consciousness. Those who are too addicted to sex life cannot observe the regulations which will lead them to Kṛṣṇa consciousness. Sex life should be restricted to persons who are married. A person whose sex life is restricted in marriage is also called a brahmacārī.

(Srimad Bhagavatam--------3:28:4-------translation and purport).

When a person is devoid of devotional service, or viṣṇu-bhakti, he takes to many sinful activities. King Purañjana left home, neglected his own wife and engaged himself in killing animals. This is the position of all materialistic men. They do not care for a married chaste wife. They take the wife only as an instrument for sense enjoyment, not as a means for devotional service. To have unrestricted sex life, the karmīs work very hard. They have concluded that the best course is to have sex with any woman and simply pay the price for her, as though she were a mercantile commodity. Thus they engage their energy in working very hard for such material acquisitions. Such materialistic people have lost their good intelligence. They must search out their intelligence within the heart. A person who does not have a chaste wife accepted by religious principles always has a bewildered intelligence.

(Srimad Bhagavatam--------4:26:17-------purport).

The actual happiness of the karmīs is sex life. They work very hard outside the home, and to satiate their hard labor, they come home to enjoy sex life. King Purañjana went to the forest to hunt, and after his hard labor he returned home to enjoy sex life. If a man lives outside the home and spends a week in a city or somewhere else, at the end of the week he becomes very anxious to return home and enjoy sex with his wife. This is confirmed in Śrīmad-Bhāgavatam: yan maithunādi-gṛhamedhi-sukhaṁ hi tuccham (S.B.7:9:45). Karmīs work very hard simply to enjoy sex. Modern human society has improved the materialistic way of life simply by inducing unrestricted sex life in many different ways. This is most prominently visible in the Western world.

(Srimad Bhagavatam--------4:26:26-------purport).

We do not find in Vedic literatures that they ever used contraceptive methods, although they were begetting hundreds of children. Checking population by contraceptive method is another sinful activity, but in this age of Kali people have become so sinful that they do not care for the resultant reactions of their sinful lives. King Purañjana lay down with his wife, Purañjanī, and begot a large number of children, and there is no mention in these verses that he used contraceptive methods. According to the Vedic scriptures the contraceptive method should be restraint in sex life. It is not that one should indulge in unrestricted sex life and avoid children by using some method to check pregnancy. If a man is in good consciousness, he consults with his religious wife, and as a result of this consultation, with intelligence, one advances in his ability to estimate the value of life. In other words, if one is fortunate enough to have a good, conscientious wife, he can decide by mutual consultation that human life is meant for advancing in Kṛṣṇa consciousness and not for begetting a large number of children. Children are called pariṇāma, or by-products, and when one consults his good intelligence he can see that his by-products should be the expansion of his Kṛṣṇa consciousness.
(Srimad Bhagavatam--------4:26:6-------purport).

After completing one's education as a brahmacārī in this way, one should give dakṣiṇā, an offering of gratitude, to one's guru, and then one may leave for home and accept the next āśrama-the gṛhastha-āśrama-or else one may continue in the brahmacarya-āśrama without adulteration. The duties for the gṛhastha-āśrama and brahmacarya-āśrama, as well as the duties for sannyāsīs, are prescribed in the śāstras. A gṛhastha is not meant to enjoy sex life without restriction. Indeed, the whole purpose of Vedic life is to become free from sexual indulgence. All the āśramas are recognized for spiritual progress, and therefore although the gṛhastha-āśrama gives a kind of license for sex life for a certain time, it does not allow unrestricted sex life. Therefore, in gṛhastha life also, there is no illicit sex. A gṛhastha should not accept a woman for sexual enjoyment. Wasting semen is also illicit sex.
(Srimad Bhagavatam--------7:12---------summary).