Good Masonic Standing
This pretty much simply means that a man has not been suspended or expelled from the Freemasons and has his dues paid to date. It can also refer to a man who is a Mason but has resigned while he was in Good Masonic Standing. Such a man can easily rejoin his old Lodge or another Pennsylvania Lodge if he desires.
If you are a Pennsylvania Mason in Good Masonic Standing you can rejoin a Lodge by submitting a Petition for Membership Only.