Is it sufficient to inform one's sister, mother, and brother about a man's marriage to a divorced woman for the marriage to be considered publicly declared, or is the sexual relationship that occurred between them considered unlawful?

Marriage is a legitimate contract with conditions and pillars. The most important of these are: that the woman's guardian contracts it in the presence of two just, male, Muslim witnesses. A marriage is not valid without a guardian or witnesses, as narrated from the Prophet, peace be upon him: "There is no marriage except with a guardian," and "There is no marriage except with a guardian and two just witnesses," and "Any woman who marries without the permission of her guardian, her marriage is void."

If marriage were to be conducted without these conditions, every fornicator could then circumvent what is forbidden. This is one of the greatest circumventions of apparent prohibitions, for fornication is one of the gravest sins, and its perpetrator is exposed to the severest punishments. Allah Almighty says: (And do not approach unlawful sexual intercourse. Indeed, it is ever an immorality and is evil as a way).

The punishment for the unmarried fornicator is one hundred lashes, and for the married fornicator, stoning to death. The Prophet, peace be upon him, informed about the punishment of fornicators in a vision he saw: that they were naked men and women in a hole like an oven, being tormented therein by fire.

Therefore, one must hasten to repent, regret, and seek forgiveness, and sever the relationship with the woman. If one wishes to marry her after repentance, the path to a legitimate marriage begins by proposing to the woman through her guardian.