As regards the ruling on oral sex, Dr. Ali Jum`ah, the current mufti of Egypt, states,

Licking, sucking and kissing spouse’s sexual organs are all allowed, as long as it gives a person sexual gratification that will keep him away from Haram (unlawful) or starring at opposite sex (marriageable). But every Muslim must keep in mind that sexual intercourse is just a lust and passion that must be satisfied in a lawful way; it’s not to be perceived as necessary as foods and drinks, as it’s the case in the Western perverted ideology.

In conclusion, it has become clear now that oral sex is not prohibited, but it is not the normal choice for committed Muslims and Muslimahs. That’s, despite that oral sex is not Haram, it is completely disgusting and does not conform to the pure taste and decency of a Muslim personality.”

This applies to Then, it should be noted that one of the main objectives of the Shari`ah is to safeguard people’s life and keep them healthy. Based on this, if it is scientifically proven that oral sex or such practices cause mouth cancer or form a danger on the health of a person who practices it, then it becomes totally prohibited.

As regards anal foreplay, Dr. Salah Al-Sawy, secretary-general of the Assembly of Muslim Jurists in America (AMJA), stated,

Approaching a woman (i.e. a wife) in sexual intercourse by way of her anus is a major sin. Almighty Allah says: ( Your wives are a tilth for you, so go into your tilth when you like, and do good beforehand for yourselves, and be careful (of your duty) to Allah, and know that you will meet Him, and give good news to the believers.)(Al-Baqarah, 2:223) The Prophet (peace and blessings be upon him) said: “Whoever approaches (in sex) a menstruating woman or a woman in her anus, he has disbelieved in what came down upon Muhammad (peace and blessings be upon him).” (At-Tirmidhi, Ibn Majah and Ahmad) Also He (peace and blessings be upon him) said to `Umar ibn Al-Khattab: “(You are free to) Go from before and behind, but avoid the rectum and menstruation.” (At–Tirmidhi and Ahmad)

As for passing the penis across the anus or placing it between the buttocks or the thighs, then this remains on the default of permissibility. This is because the basic ruling is the permissibility with regards to a man’s enjoyment with his spouse. Nothing is excluded from this ruling except menstruation and the anus as the Prophet (peace and blessings be upon him) said.