Malachi 2:10
Have we not all one father? hath not one God created us? why do we deal treacherously every man against his brother, by profaning the covenant of our fathers? Have we not all one father? hath not one God created us? why do we deal treacherously every man against his brother, by profaning the covenant of our fathers?
All people have one Father, and one God created them all, and that shared creation makes them brothers to one another. Because of that common origin and brotherhood, no one is to deal treacherously with another, betraying a fellow brother. To act so faithlessly toward a brother is to profane the covenant handed down from the fathers, breaking faith with what was inherited together.
In its setting this charge stands together with the failure of priests and leaders who corrupted the covenant of Levi. They did not keep God's ways, and they showed partiality in applying the law, turning instruction aside for favor.
In its setting Judah's treachery also included profaning the holiness belonging to the Lord by marrying those devoted to foreign gods. That union with worshipers of strange gods was disloyalty to covenant faithfulness. Such disloyalty made their offerings unacceptable to God, so He would not receive what they brought.