In refutation to the accusations made towards A'isha (ra), the Prophet (SAW) wife ...

Umar said that A'isha was undoubtedly chaste and pure ... 
And that she had been slandered ... 

When asked how he knew, he replied:

O Messenger of Allah, once you were praying .... 
You stopped and explained that Archangel Gabriel had come and informed you that there was some dirt in your slippers ... 
If there were some impurity in A'isha, God certainly would have informed you ...