What is the required expiation (Kaffarah) for one capable of freeing a slave due to Zihar?

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The expiation for a capable man due to Zihar is the freeing of a slave, and nothing else suffices. There is no known disagreement among the scholars on this point. The basis for this ruling is the Almighty's saying: {And those who pronounce Zihar of their wives and then return to what they said, then the freeing of a slave before they touch one another} (Quran 58:3), down to {But whoever cannot find [one], then fasting for two successive months before they touch one another} (Quran 58:4). The Prophet, peace be upon him, commanded Aws ibn al-Samit to free a slave upon making Zihar, and only directed him to fasting when he stated he could not find one. The ability to free a slave negates the transition to the alternative expiation (fasting), similar to how the presence of water prevents the transition to Tayammum (dry ablution). This is the apparent position of the Madhhab and the view of Al-Hasan, Malik, Shafi'i, Ishaq, and Abu Ubayd.