And Jahm and his Jabriyyah followers said that this act lies within the Lord’s power, but not the servant’s. Likewise, al-Ash'arī and his followers said that the power which produces the act is the Lord’s power, not the servant’s.

The Mu'tazilites argued that if the act lay within the power of both, then, if one willed it while the other was averse to it—for example, if the Lord willed to move the servant while the servant was averse to being moved—the act would necessarily both exist and not exist. For an act within an agent’s power characteristically comes into existence when his motives for it are fully present, and remains nonexistent when his impulse against it is fully present. Thus, if the act lay within both the servant’s power and Allah’s power, then, if Allah willed its occurrence while the servant was averse to it, it would necessarily exist because the motives for it were present, and not exist because the opposing impulse was present. This is impossible.

The Jabriyyah answered this with the response mentioned by al-Rāzī: remaining nonexistent when the opposing impulse is present is not conceded without qualification; rather, it is necessary only if no other independent cause takes its place,