In material life everyone is desirous of sense gratification; therefore, a person who gets an object of sense gratification without endeavor should not refuse to accept it. Kardama Muni was not meant for sense gratification, yet he aspired to marry and prayed to the Lord for a suitable wife. This was known to Svāyambhuva Manu. He indirectly convinced Kardama Muni: "You desire a suitable wife like my daughter, and she is now present before you. You should not reject the fulfillment of your prayer; you should accept my daughter."
(Srimad Bhagavatam-----3:22:12-----purport).

The general procedure of Vedic marriage is that a father offers his daughter to a suitable boy. That is a very respectable marriage. A boy should not go to the girl's father and ask for the hand of his daughter in marriage. That is considered to be humbling one's respectable position. Svāyambhuva Manu wanted to convince Kardama Muni, since he knew that the sage wanted to marry a suitable girl: "I am offering just such a suitable wife. Do not reject the offer, or else, because you are in need of a wife, you will have to ask for such a wife from someone else, who may not behave with you so well. In that case your position will be humbled."
(Srimad Bhagavatam-----3:22:13-----purport).

The principle of brahmacarya is celibacy. There are two kinds of brahmacārīs. One is called naiṣṭhika-brahmacārī, which means one who takes a vow of celibacy for his whole life, whereas the other, the upakurvāṇa-brahmacārī, is a brahmacārī who takes the vow of celibacy up to a certain age. For example, he may take the vow to remain celibate up to twenty-five years of age; then, with the permission of his spiritual master, he enters married life. Brahmacarya is student life, the beginning of life in the spiritual orders, and the principle of brahmacarya is celibacy. Only a householder can indulge in sense gratification or sex life, not a brahmacārī. Svāyambhuva Manu requested Kardama Muni to accept his daughter, since Kardama had not taken the vow of naiṣṭhika-brahmacarya. He was willing to marry, and the suitable daughter of a high royal family was presented.
(Srimad Bhagavatam-----3:22:14-----purport).

There were many considerations by Kardama Muni before accepting the daughter of Svāyambhuva Manu. Most important is that Devahūti had first of all fixed her mind on marrying him. She did not choose to have any other man as her husband. That is a great consideration because female psychology dictates that when a woman offers her heart to a man for the first time, it is very difficult for her to take it back. Also, she had not married before; she was a virgin girl. All these considerations convinced Kardama Muni to accept her. Therefore he said, "Yes, I shall accept your daughter under religious regulations of marriage." There are different kinds of marriages, of which the first-class marriage is held by inviting a suitable bridegroom for the daughter and giving her in charity, well dressed and well decorated with ornaments, along with a dowry according to the means of the father. There are other kinds of marriage, such as gāndharva marriage and marriage by love, which are also accepted as marriage. Even if one is forcibly kidnapped and later on accepted as a wife, that is also accepted. But Kardama Muni accepted the first-class way of marriage because the father was willing and the daughter was qualified. She had never offered her heart to anyone else. All these considerations made Kardama Muni agree to accept the daughter of Svāyambhuva Manu.
(Srimad Bhagavatam-----3:22:15-----purport).

Kardama Muni wanted to marry Devahūti in the recognized manner of marriage prescribed in the scriptures. As stated in the Vedic scriptures, the first-class process is to call the bridegroom to the home of the bride and hand her to him in charity with a dowry of necessary ornaments, gold, furniture and other household paraphernalia. This form ofmarriage is prevalent among higher-class Hindus even today and is declared in the śāstras to confer great religious merit on the bride's father. To give a daughter in charity to a suitable son-in-law is considered to be one of the pious activities of a householder. There are eight forms of marriage mentioned in the scripture Manu-smṛti, but only one process of marriage, brāhma or rājasika marriage, is now current. Other kinds of marriage-by love, by exchange of garlands or by kidnapping the bride-are now forbidden in this Kali age. Formerly, kṣatriyas would, at their pleasure, kidnap a princess from another royal house, and there would he a fight between the kṣatriya and the girl's family; then, if the kidnapper was the winner, the girl would be offered to him for marriage. Even Kṛṣṇa married Rukmiṇī by that process, and some of His sons and grandsons also married by kidnapping. Kṛṣṇa's grandsons kidnapped Duryodhana's daughter, which caused a fight between the Kuru and Yadu families. Afterward, an adjustment was made by the elderly members of the Kuru family. Such marriages were current in bygone ages, but at the present moment they are impossible because the strict principles of kṣatriya life have practically been abolished. Since India has become dependent on foreign countries, the particular influences of her social orders have been lost; now, according to the scriptures, everyone is a śūdra.
(Srimad Bhagavatam-----3:22:16-----purport).

Kardama Muni expressed his desire for a very beautiful wife to Emperor Svāyambhuva and accepted the Emperor's daughter for marriage. Kardama Muni was in the hermitage practicing complete celibacy as a brahmacārī, and although he had the desire to marry, he did not want to be a householder for the whole span of his life because he was conversant with the Vedic principles of human life. According to Vedic principles, the first part of life should be utilized in brahmacarya for the development of character and spiritual qualities. In the next part of life, one may accept a wife and beget children, but one should not beget children like cats and dogs.
(Srimad Bhagavatam-----3:22:19-----purport).

This is one reason to beget a child. Another reason is that a highly enlightened parent can train a child in Kṛṣṇa consciousness so that the child will not have to come back again to this miserable world. Parents should see to it that the child born of them does not enter the womb of a mother again. Unless one can train a child for liberation in that life, there is no need to marry or produce children. If human society produces children like cats and dogs for the disturbance of social order, then the world becomes hellish, as it has in this age of Kali. In this age, neither parents nor their children are trained; both are animalistic and simply eat, sleep, mate, defend, and gratify their senses. This disorder in social life cannot bring peace to human society. Kardama Muni explains beforehand that he would not associate with the girl Devahūti for the whole duration of his life. He would simply associate with her until she had a child. In other words, sex life should be utilized only to produce a nice child, not for any other purpose. Human life is especially meant for complete devotion to the service of the Lord. That is the philosophy of Lord Caitanya.
(Srimad Bhagavatam-----3:22:19-----purport).

Marrying and begetting a child is considered to liquidate one's debts to the family in which one is born. There are many debts which are imposed upon a child just after his birth. There are debts to the family in which one is born, debts to the demigods, debts to the Pitās, debts to the ṛṣis, etc. But if someone engages only in the service of the Supreme Lord, the Personality of Godhead, who is actually worshipable, then even without trying to liquidate other debts, one becomes free from all obligations. Kardama Muni preferred to devote his life as a servant of the Lord in paramahaṁsa knowledge and to beget a child only for that purpose, not to beget numberless children to fill up the vacancies in the universe.
(Srimad Bhagavatam-----3:22:20-----purport).

The custom of giving one's daughter in charity with a dowry is still current in India. The gifts are given according to the position of the father of the bride. Pāribarhān mahā-dhanān means the dowry which must be awarded to the bridegroom at the time of marriage. Here mahā-dhanān means greatly valuable gifts befitting the dowry of an empress. The words bhūṣā-vāsaḥ paricchadān also appear here. Bhūṣā means "ornaments," vāsaḥ means "clothing," and paricchadān means "various household articles." All things befitting the marriage ceremony of an emperor's daughter were awarded to Kardama Muni, who was until now observing celibacy as a brahmacārī. The bride, Devahūti, was very richly dressed with ornaments and clothing.
In this way Kardama Muni was married with full opulence to a qualified wife and was endowed with the necessary paraphernalia for household life. In the Vedic way of marriage such a dowry is still given to the bridegroom by the father of the bride; even in poverty-stricken India there are marriages where hundreds and thousands of rupees are spent for a dowry. The dowry system is not illegal, as some have tried to prove. The dowry is a gift given to the daughter by the father to show good will, and it is compulsory. In rare cases where the father is completely unable to give a dowry, it is enjoined that he must at least give a fruit and a flower. As stated in Bhagavad-gītā, God can also be pleased even by a fruit and a flower. When there is financial inability and no question of accumulating a dowry by another means, one can give a fruit and flower for the satisfaction of the bridegroom.
(Srimad Bhagavatam-----3:22:23-----purport).

A father always remains in anxiety until he can hand over his grownup daughter to a suitable boy. A father and mother's responsibility for children continues until theymarry them to suitable spouses; when the father is able to perform that duty, he is relieved of his responsibility.
(Srimad Bhagavatam-----3:22:24-----purport).