About to open his mouth - In self-defense, ever ready to vindicate his conduct.
A matter of wrong - Injustice, or crime, such as could be properly brought before a court of justice.
Or wicked lewdness - Any flagrant and gross offence. The word used here occurs nowhere else in the New Testament. It denotes properly an act committed by him who is skilled, facile, or an adept in iniquity an act of a veteran offender. Such crimes Gallio was willing to take cognizance of.
Reason would ... - Greek: “I would bear with you according to reason.” There would be propriety or fitness in my hearing and trying the case. Thai is, it would fall within the sphere of my duty, as appointed to guard the peace, and to punish crimes.