Thanks Bender for quoting the NIV version: Deuteronomy 20:13-14 New International Version (NIV)
Let me see this in the KJV: De 20:17 But thou shalt utterly destroy them; namely, the Hittites, and the Amorites, the Canaanites, and the Perizzites, the Hivites, and the Jebusites; as the LORD thy God hath commanded thee:
Ge 15:16 But in the fourth generation they shall come hither again: for the iniquity of the Amorites is not yet full.
It seems to me GOD gave these people groups over 400 years to repent of their evil ways. Even when Jericho was such a city, Rahab, a prostitute was saved along with her family because she had faith in God, the only one saved from destruction of Jericho (see Joshua chapter 2). Since God is grace and mercy as well as just and a judge over sins, is not GOD able to spare people in cities as He see fit? or even remove their probation of living?
Ps 7:14 Behold, he travaileth with iniquity “aven” , and hath conceived mischief, and brought forth falsehood.
If you study the Hebrew there is a Hebrew word called “aven” which refers to the epi-genetic potential that drives all our genetic expressions, and records all our propensities of ourselves and our parents. This epi-genetic potential kicks in when you are over puberty, and unless GOD drives out these propensities, you become as your parents before you, doing the same sinful habits as they did. After 400 years, is there any possibility of a child seeking God over his inherited potential from sinful parents before him? Rahab is one example, so God is able to save some, but others choose to be lost, because of their own doings. Hope this helps. Shalom