What is the required number of witnesses for testimony regarding apostasy (Riddah)?

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The testimony concerning apostasy is accepted from two just male witnesses, which is the position held by the majority of scholars. This view is adopted by Malik, Al-Awza'i, Al-Shafi'i, and the Companions of Ra'y (the Hanafi school). The evidence for accepting two witnesses is that this testimony pertains to an offense other than adultery (Zina), similar to testimony regarding theft, which requires only two witnesses. The comparison to adultery is unsound because the requirement of four witnesses in Zina is specifically due to the penalty of death, which is not the primary issue in apostasy. Furthermore, the penalty for slander (Qadhf) regarding Zina requires eighty lashes, unlike slander regarding apostasy.