Praise be to Allah.
Al-Shafi`’i and his companions quote as evidence for that the verse which reads,
“and prohibits them as unlawful Al-Khabaith (i.e. all evil and unlawful as regards things, deeds, beliefs, persons and foods),” [al-A’raf 7:157 – interpretation of the meaning]
These are things which the Arabs find repulsive. And they quote as evidence the words of the Prophet (peace and blessings of Allah be upon him): “(There are) five animals, all of which are evil and should be killed in the Haram (sanctuary of Makkah): crows, kites [a kind of bird], scorpions, rats and vicious dogs .” (Narrated by al-Bukhari and Muslim from the report of `Aishah, Hafsah and Ibn ‘Umar).
Umm Shurayk narrated that the Prophet (peace and blessings of Allah be upon him) commanded the killing of lizards. (Narrated by al-Bukhari and Muslim). With regard to the verse (interpretation of the meaning):
“Say (O Muhammad): ‘I find not in that which has been revealed to me anything forbidden to be eaten by one who wishes to eat it, unless it be Maytah (a dead animal) or blood poured forth (by slaughtering or the like), or the flesh of swine (pork); for that surely, is impure or impious (unlawful) meat (of an animal) which is slaughtered as a sacrifice for others than Allah (or has been slaughtered for idols, or on which Allah’s Name has not been mentioned while slaughtering).” [al-An’am 6:145], al-Shafi`i and other scholars said: what this refers to is things which you used to eat and regard as good. Al-Shafi`i said: “this is the most likely meaning of the verse, based on the Sunnah.
And Allah knows best.