Deuteronomy 13:5
3 You must not listen to the words of that prophet or dreamer, for the Lord your God will be testing you to see if you love him with all your mind and being. 4 You must follow the Lord your God and revere only him; and you must observe his commandments, obey him, serve him, and remain loyal to him. 5 As for that prophet or dreamer, he must be executed because he encouraged rebellion against the Lord your God who brought you from the land of Egypt, redeeming you from that place of slavery, and because he has tried to entice you from the way the Lord your God has commanded you to go. In this way you must purge evil from among you. 6 Suppose your own full brother, your son, your daughter, your beloved wife, or your closest friend should seduce you secretly and encourage you to go and serve other gods that neither you nor your ancestors have previously known, 7 the gods of the surrounding people (whether near you or far from you, from one end of the earth to the other).
Judges 20:13
11 So all the men of Israel gathered together at the city as allies. 12 The tribes of Israel sent men throughout the tribe of Benjamin, saying, “How could such a wicked thing take place? 13 Now, hand over the good-for-nothings in Gibeah, so we can execute them and purge Israel of wickedness.” But the Benjaminites refused to listen to their Israelite brothers. 14 The Benjaminites came from their cities and assembled at Gibeah to make war against the Israelites. 15 That day the Benjaminites mustered from their cities 26,000 sword-wielding soldiers, besides 700 well-trained soldiers from Gibeah.
Notes and References
"... At the end of his discussion of the man in incest, Paul inserts his next citation. This citation from Deuteronomy 17:7 is found in 1 Corinthians 5:13 which reads as follows, “God judges those outside. ‘Purge the evil person from among you.’” The passage noticeably supports the ideas of 1 Corinthians 5:12. In this text Paul is calling for the Corinthian church to judge those in their midst. When Deuteronomy 17:7 is considered in relation to its other broader Jewish context, it becomes apparent that the ideas from this text extend even further than simply 1 Corinthians 5:12. The exhortation to purge certain people from the midst of God’s people is a frequent one in the book of Deuteronomy. Indeed, Deuteronomy 17:7 is representative of other passages in Deuteronomy where the theme of exclusion is found (compare Deuteronomy 13:5; 19:19; 21:21; 22:21; 24:7; compare Judges 20:13). When the idea of expulsion is considered throughout the book of Deuteronomy, God’s people are exhorted to exclude a number of deviant behaviors such as: the sexually immoral (Deuteronomy 22:21–22, 30), idolater (Deuteronomy 13:1–5; 17:2–7), reviler (Deuteronomy 19:16–19), drunkard (21:18–21), and robber (Deuteronomy 24:7) ..."
Williams III, H. H. Drake "Light Giving Sources: Examining the Extent of Scriptural Citation and Allusion Influence in 1 Corinthians" in Porter, Stanley E. (ed.) Paul: Jew, Greek, and Roman (pp. 7-37) Brill, 2008