Ellicott's Commentary for English Readers - Deuteronomy 13:9
(9) Thine hand shall be first upon him to put him to death.—A law tending to prevent false accusation. Where the witness is obliged to carry out himself, or to aid in carrying out, the sentence he demands, secret accusation is impossible; and it is far less easy to pervert the law in order to prosecute a private quarrel. read more
Ellicott's Commentary for English Readers - Deuteronomy 13:6
(6) If thy brother.—The substance of this law is that individual idolaters might be executed in Israel. It justifies Jehu and Jehoiada in destroying Baal out of Israel and Judah (2 Kings 10:19-27; 2 Kings 11:18). It also accounts for the covenant made in the time of Asa (2 Chronicles 15:13), that whosoever would not serve the Lord God of Israel should be put to death whether man or woman.The law may seem harsh, but its principle is reproduced in the Gospel: “He that loveth father or mother more... read more