A couple who are physically incapable of having children may, of course, marry, since the procreation of children is not the only purpose of marriage. However, it would be contrary to the spirit of the Teachings for a couple to decide voluntarily never to have any children.
(Universal House of Justice, Lights of Guidance, p. 379)
Also a father and mother endure the greatest troubles and hardships for their children; and often when the children have reached the age of maturity, the parents pass on to the other world. Rarely does it happen that a father and mother in this world see the reward of the care and trouble they have undergone for their children. Therefore, children, in return for this care and trouble, must show forth charity and beneficence, and must implore pardon and forgiveness for their parents. So you ought, in return for the love and kindness shown you by your father, to give to the poor for his sake, with greatest submission and humility implore pardon and remission of sins, and ask for the supreme mercy.
(Adib Taherzadeh, The Covenant of Bahá’u’lláh, p. 17)
Both Bahá’u’lláh and the Bab emphasize the need of children in marriage. The latter, for example, states that to beget children is the highest physical fruit of man’s existence. But neither say whether the number of children should be limited or not. Or if it is to be limited what is the proper method to be used.
(Shoghi Effendi, Unrestrained as the Wind, p. 132)
Children are the most precious treasure a community can possess, for in them are the promise and guarantee of the future. They bear the seeds of the character of future society which is largely shaped by what the adults constituting the community do or fail to do with respect to children. They are a trust no community can neglect with impunity. An all-embracing love of children, the manner of treating them, the quality of attention shown them, the spirit of adult behavior toward them - - these are all among the vital aspects of the requisite attitude. Love demands discipline, the courage to accustom children to hardship, not to indulge their whims or leave them entirely to their own devices. An atmosphere needs to be maintained in which children feel that they belong to the community and share in its purpose. They must lovingly but insistently be guided to live up to Bahá’í standards, to study and teach the Cause in ways that are suited to their circumstances.
(Universal House of Justice, Ridván Message, 2000)
It is highly important for man to raise a family. So long as he is young, because of youthful self-complacency, he does not realize its significance, but this will be a source of regret when he grows old.
(‘Abdu’l-Bahá, Lights of Guidance, p. 219)
Men must become pure in heart to know God. The teachings have had great effect. Spiritual souls! Tender souls! The hearts of all children are of the utmost purity. They are mirrors upon which no dust has fallen. But this purity is on account of weakness and innocence, not on account of any strength and testing, for as this is the early period of their childhood, their hearts and minds are unsullied by the world. They cannot display any great intelligence. They have neither hypocrisy nor deceit. This is on account of the child’s weakness, whereas the man becomes pure through his strength. Through the power of intelligence he becomes simple; through the great power of reason and understanding and not through the power of weakness he becomes sincere. When he attains to the state of perfection, he will receive these qualities; his heart becomes purified, his spirit enlightened, his soul is sensitized and tender—all through his great strength. This is the difference between the perfect man and the child. Both have the underlying qualities of simplicity and sincerity—the child through the power of weakness and the man through the power of strength.
(‘Abdu’l-Bahá, The Promulgation of Universal Peace, p. 52)
The new child which will soon be given to you by God is, indeed, a divine blessing, of which you should feel proud, and of the manifold responsibilities and obligations which it necessarily entails you should become fully aware. It is now that you can truly say that you have a family life. Without a child there can be no family, and through him the bonds of love and of service can be truly and strongly maintained between the wife and husband.
(Universal House of Justice to an individual believer, 5 June 1974)