What is the ruling on striking someone who insults Allah – when they are neither angry nor overwhelmed by circumstances – until they stop doing so?

"Swearing at Allah the Almighty is an act of disbelief that expels one from the faith. Its perpetrator apostatizes from Islam, and the ruler must execute him after seeking his repentance. People are obligated to denounce this evil, but enforcing the حد (punishment) is not their prerogative. Striking the one who curses is not considered changing the evil with one's hand; rather, it is a punishment, and punishments are administered by the ruler or his representative."