What is the ruling when one is certain they entered the time of Dhuhr prayer but is uncertain about the sequence of events regarding their prior state of purity?
Chapter on What Nullifies Purification
Al-Mughni
Book of Purification
Primary text
If one is certain they entered the time of Dhuhr prayer and is certain their previous state of purity was broken, necessitating ablution, but is uncertain about which event (the first purification or the subsequent breaking) occurred first, one must investigate the prior state. If the person was pure before Dhuhr began, they remain in a state of purity. This is because they are certain they broke that specific prior purification, and then performed a new ablution, as one cannot perform ablution for an impurity while maintaining a previous state of purity. The breaking of this second purification is doubtful, and certainty (the previous state of purity) is not removed by doubt.
Supporting text
If the person was in a state of impurity before Dhuhr began, they are currently considered impure. This is because they are certain they transitioned from impurity to a state of purity, and then broke that purity. The state of purity following the breaking is doubtful.