Translation:

2. The woman and the man guilty of adultery or fornication flog each of them with a hundred stripes: let not compassion move you in their case in a matter prescribed by Allah if ye believe in Allah and the Last Day: and let a party of the Believers witness their punishment.

Notes (Tafseer)

2954. Zina includes sexual intercourse between a man and a woman not married to each other. It therefore applies both to adultery (which implies that one or both of the parties are married to a person or persons other than the ones concerned) and to fornication, which, in its strict signification, implies that both parties are unmarried. The law of marriage and divorce is made easy in Islam, so that there may be the less temptation for intercourse outside the well-defined incidents of marriage. This makes for greater self-respect for both man and woman. Other sex offences are also punishable, but this Section applies strictly to Zina as above defined. Although zina covers both fornication and adultery, in the opinion of Muslim jurists, the punishment laid down here applies only to unmarried persons. As for married persons, their punishment, according to the Sunnah of the Prophet (peace be on him), is stoning to death.

2955. Cf. iv. 15, and n. 523.

2956. The punishment should be open, in order to be deterrent.