New Defender's Study Bible Notes
23:6 all that is written. As at the beginning, when God admonished Joshua to observe everything Moses had written in the book of the law (Joshua 1:7, 8), so Joshua at the end of his ministry of leadership reminds the people of the absolute authority of everything written in the books we call the Pentateuch, from the record of creation to the last words of Moses.
23:12 marriages. It has always been contrary to God’s will for believers to marry unbelievers. Note II Corinthians 6:14; I Corinthians 7:39; Amos 3:3; etc.