Yes there is a rule, a standard, a way of life to keep to. It is not what you think or what perhaps man teaches and certainly not what the false teachers have been pressurising the Galatian churches with, especially that male converts must be circumcised to be accepted by God.
“Neither circumcision nor uncircumcision means anything; what counts is the new creation. Peace and mercy to all who follow this rule—tothe Israel of God.” (Galatians 6:15-16)
This then is the rule: Nothing else matters or is worth anything compared the gospel of the cross of the Lord Jesus Christ! Do you know this gospel? Is it seen in your life more than your religious effort to be accepted by God? If you can’t see this gospel in people then it probably isn’t there.
It is the only way you will have peace from those who lay burdens on you and not lift them off you.
It is the only way you will have mercy knowing the healing and forgiveness for your sins and attempted recompense for your sins.
It is the only way you will experience being the true Israel, the Abrahamic child and in particular the heir of God’s promises for your life.
That’s the big rule.

