What is the sound legal ruling that a Muslim can be confident in regarding banking transactions, in light of the differing fatwas between those who permit them, such as the Shaykh of Al-Azhar, and those who prohibit them?

The Sharia texts from the Quran, Sunnah, and scholarly consensus have converged on the prohibition of usury (riba), stating that it is among the gravest sins. Allah Almighty says: "O you who have believed, fear Allah and give up what remains [due to you] of riba, if you should be believers. And if you do not, then be informed of a war [against you] from Allah and His Messenger." The Prophet (peace be upon him) mentioned usury among the seven destructive sins. Accordingly, if banks deal with usury, it is not permissible to deal with them except in cases of extreme necessity.