How sound is the tradition narrated from 'Umar ibn al-Khattab: "You do not overcome your enemy by numbers, nor by equipment, but you overcome them by this religion. If you and your enemy become equal in sins, then victory will be for the stronger"?

This narration has been transmitted in history books from Umar (may Allah be pleased with him) to his governors and army commanders. In it, he advises them to fear Allah and to beware of sins, because the sins of the army are more to be feared for them than their enemy. The narration has also been attributed to Umar ibn Abd al-Aziz. It is stated within it that Umar (may Allah be pleased with him) wrote to Abu Ubaydah ibn al-Jarrah that victory is not achieved by numbers and equipment, but rather by the help, victory, grace, and favor of Allah.