Does the husband's doubt about uttering a triple divorce remove the certainty of the marriage? And what is the ruling on one who intended to consider a triple divorce out of piety, then wished to retract this intention and instead adopt the principle that certainty is not removed by doubt?

Divorce does not occur based on doubt, whether it is pronounced as three or one, conditional or unconditional. There is no validity to what happens due to obsessive thoughts regarding the occurrence of divorce as a precaution or out of piety. For divorce does not occur by inner speech without uttering it. One must beware of obsessive thoughts concerning matters of divorce.