When the mind is polluted by fruitive activity, the living entity wants to be elevated from one material position to another. Generally, everyone is involved in working hard day and night to improve his economic condition. Even when one understands the Vedic rituals, he becomes interested in promotion to heavenly planets, not knowing that one’s real interest lies in returning home, back to Godhead. By acting on the platform of fruitive activity, one wanders throughout the universe in different species and forms. Unless he comes in contact with a devotee of the Lord, a guru, he does not become attached to the service of Lord Vāsudeva. Knowledge of Vāsudeva requires many births to understand. As confirmed in Bhagavad-gītā (7.19): vāsudevaḥ sarvam iti sa mahātmā sudurlabhaḥ. After struggling for existence for many births one may take shelter at the lotus feet of Vāsudeva, Kṛṣṇa. When this happens, one actually becomes wise and surrenders unto Him. That is the only way to stop the repetition of birth and death. This is confirmed in Caitanya-caritāmṛta (Madhya 19.151) in the instructions given by Śrī Caitanya Mahāprabhu to Śrīla Rūpa Gosvāmī at Daśāśvamedha-ghāṭa.
guru-kṛṣṇa-prasāde pāya bhakti-latā-bīja
The living entity wanders throughout different planets in different forms and bodies, but if by chance he comes in contact with a bona fide spiritual master, by the grace of the spiritual master he receives Lord Kṛṣṇa’s shelter, and his devotional life begins.
In the lowest stage of devotional life, one is not an unalloyed devotee. Anyābhilāṣitā-śūnyaṁ jñāna-karmādy-anāvṛtam: to be an unalloyed devotee, one must be freed from all material desires and untouched by fruitive activity and speculative knowledge. On the lower platform, one may sometimes be interested in philosophical speculation with a tinge of devotion. However, at that stage, one is still interested in sense gratification and is contaminated by the modes of material nature. The influence of māyā is so strong that even a person advanced in knowledge actually forgets that he is Kṛṣṇa’s eternal servant. Therefore he remains satisfied in his householder life, which is centered around sexual intercourse. Conceding to a life of sex, he agrees to suffer all kinds of material miseries. Due to ignorance, one is thus bound by the chain of material laws.
Sex serves as the natural attraction between man and woman, and when they are married, their relationship becomes more involved. Due to the entangling relationship between man and woman, there is a sense of illusion whereby one thinks, “This man is my husband,” or “This woman is my wife.” This is called hṛdaya-granthi, “the hard knot in the heart.” This knot is very difficult to undo, even though a man and woman separate either for the principles of varṇāśrama or simply to get a divorce. In any case, the man always thinks of the woman, and the woman always thinks of the man. Thus a person becomes materially attached to family, property, and children, although all of these are temporary. The possessor, unfortunately, identifies with his property and wealth. Sometimes, even after renunciation, one becomes attached to a temple or to the few things that constitute the property of a sannyāsī, but such attachment is not as strong as a family attachment. The attachment to the family is the strongest illusion. In the Satya-saṁhitā, it is stated:
mucyante strī-sahāyinaḥ
bodhyante kecanaiteṣāṁ
viśeṣam ca vido viduḥ
Sometimes it is found among exalted personalities like Lord Brahmā that the wife and children are not a cause of bondage. On the contrary, the wife actually helps further spiritual life and liberation. Nonetheless, most people are bound by the knots of the marital relationship, and consequently, they forget their relationship with Kṛṣṇa.
When, by associating with sādhus and engaging in devotional service, one is gradually freed from the material conception due to knowledge, practice, and detachment, the knot of attachment in the heart is slackened. Thus one can get freed from conditional life and become eligible to return home, back to Godhead.
(Srimad Bhagavatam 5.5.6 to 9 Purport)