The Kitáb-i-Aqdas - The Most Holy Book
Index term: consent of parents, under Marriage
k65.
It hath been laid down in the Bayán that marriage is dependent upon the consent of both parties. Desiring to establish love, unity and harmony amidst Our servants, We have conditioned it, once the couple's wish is known, upon the permission of their parents, lest enmity and rancour should arise amongst them. And in this We have yet other purposes. Thus hath Our commandment been ordained.
n92.
We have conditioned it . . . upon the permission of their parents
In a letter written on his behalf, Shoghi Effendi has commented on this provision of the law:

Bahá'u'lláh has clearly stated the consent of all living parents is required for a Bahá'í marriage. This applies whether the parents are Bahá'ís or non-Bahá'ís, divorced for years or not. This great law He has laid down to strengthen the social fabric, to knit closer the ties of the home, to place a certain gratitude and respect in the hearts of the children for those who have given them life and sent their souls out on the eternal journey towards their Creator.
q13.
 
Question: Is the consent of the parents on both sides prerequisite to marriage, or is that of the parents on one side sufficient? Is this law applicable only to virgins or to others as well?
Answer: Marriage is conditional upon the consent of the parents of both parties to the marriage, and in this respect it maketh no difference whether the bride be a virgin or otherwise.