13:1 In that day God would open a fountain for the complete spiritual cleansing of the Israelites, both for their moral sins and for their ritual uncleanness (cf. Ezek. 47). The figure of a fountain pictures abundant cleansing that would continue indefinitely. This will be the fulfillment of God's promise to forgive the sins of His people Israel in the New Covenant (3:4, 9; Jer. 31:34; Ezek. 36:25; cf. Zech. 3:4, 9; Rom. 11:26). "The blood of Jesus . . . cleanses us from all sin"(1 John 1:7). The cleansing is available now, but God will cleanse multitudes of Israelites in the future, after they turn to their Messiah in faith (12:10-14).
13:2 At that time the Lord also promised to remove idolatry, false prophets, and unclean spirits from the land. There would be external cleansing as well as internal. The Jews would "no longer ascribe supernatural powers to mere things, nor worship them as divine"(cf. 10:2-3; Jer. 23:30-32; 27:9-10; Ezek. 13:1-14:11).267False prophets, as is clear from the context, would not mislead the people (cf. Matt. 24:4-5, 11, 15, 23-24; 2 Thess. 2:2-4; Rev. 9:20; 13:4-15). The unclean spirits are the diviners, mediums, and demons who confused and afflicted the people in the past.
"The reference to the banishment of the unclean spirits out of the land . . . is the only passage in Scripture which explicitly refers to the imprisonment of demons during the kingdom age. But since Satan is remanded to the abyss (the prison house of evil spirits) during this era, as is clearly declared in Revelation 20:1-3, it is a necessary corollary that his demon aids shall also share the same fate."268
13:3 If anyone would try to play the part of a false prophet, his own parents, those closest to him, would put him to death. This was what God had commanded the Israelites to do to false prophets (Deut. 13:6-9). They would pierce the false prophets fatally as they had formerly pierced the Messiah fatally (12:10).
13:4-5 This dangerous situation for the false prophets would lead them to hide their identity as prophets. They would not identify themselves in traditional ways (cf. 2 Kings 1:8) but would deny that they were prophets. They would go so far as claiming to have been sold into slavery as field hands when they were only boys, so they could not possibly be prophets.
13:6 Sometimes false prophets cut themselves to arouse prophetic ecstasy, to increase ritual potency, or to identify themselves with a particular god (cf. Lev. 19:28; 21:5; Deut. 14:1; 1 Kings 18:28; Jer. 16:6; 41:5; 48:37). If someone saw such marks on a false prophet's body in that future day, the false prophet might claim that he had received his injuries by accident in a friend's house.269
Though some expositors believed this verse describes Messiah and His wounds, the preceding context and lack of any New Testament citation of the verse in relation to Messiah argue against this view.270
"As is always the case with genuine conversion there are both negative and positive aspects. The positive consists of the restoration to fellowship that takes place when sin has been forgiven (v. 1). The negative involves the removal of those habits and attitudes that occasioned the interruption of fellowship between God and His people in the first place (vv. 2-6)."271
