Sin had not reached its full measure?

Thanks for your question. God sovereignly times the arrival of his divine judgment with the fullness of the sin(s) to be judged. God is not quick tempered; he is patient, even with the wicked (Rom 2:4). However, there comes a time when the sins of the wicked ripen to full harvest (Joel 3:13; Rev 14:14-15,18-20). That is the time of God's decisive judgment, which is always holy, righteous, and good (Rom 7:12).

The Amorites were a very wicked people (Deut 9:5). They were unrepentant. The Hebrew word translated as "iniquity" in Genesis 15:16 is avon, meaning 'iniquity, guilt, or punishment for iniquity.' Part of their iniquity is recounted for us in Numbers 21:21-26 and Deuteronomy 20:16-18. In addition, they worshipped false gods, such as Baal. The Apostle Paul later wrote in 1 Corinthians 10:20 concerning things which the Gentiles sacrificed to demons (cf. Lev 17:7; Deut 32:17; Psa 106:37). Clearly, this was an abomination, which led in time to other societal abominations, such as child sacrifice (Lev 20:1-5; cf. Deut 12:31; 18:9-10; 2 Kings 16:3; 21:6; Isa 57:5; Jer 7:30-31; 19:5; 32:35; Ezek 16:20-21; 23:36-39, etc.). So, over time the vat of wrath was filled.

The wicked have a measure of iniquity to fill up; such as Sodom whose sin was great and exceedingly grave (Gen 18:20). Some fill up the vat of wrath quicker, while others slower. In either case, God waits patiently and bears with the wicked (Rom 9:22). However, when the time is full, he holds off no longer, but delivers vengeance upon them (Matt 23:32). So, while the guilt of man is accumulated little by little, when the time comes God moves swiftly, like a thief in the night (cf. 1 Thess 5:1-2).

We often ask, "Why do the wicked live such long lives, why do we see so many of them prosper?" Why do the United States and other nations seem to go unpunished for all of their evil? For instance, LifeNews cites that Planned Parenthood CEO Cecile Richards is proud of their record of murdering 7 + million babies. [1] The United States by their laws support such abomination! Why does God allow this? The answer is seen here in Genesis 15:16; their sin has not yet reached it full measure. But, even those who run nations and corporations are "storing up wrath" for "the day of wrath when God's righteous judgment will be revealed" (Rom 2:5; 1 Thess 2:16).

Wrath, like wealth, is not all exhausted at once, it remains in a sealed vault to be used at some future time (2 Pet 3:7). Like snow that accumulates upon a mountain top flake by flake, it builds and builds until that day of a great avalanche. So, he that continues to sin is building up wrath against himself. But, overwhelming judgment will surely come. Their damnation is just (Rom 3:8). The wages of sin is death (Rom 3:23).

References:

[1] Ertelt, Steven. LifeNews "Cecile Richards: Planned Parenthood "Proudly" Kills 7 Million Babies in Abortions, "We're Just Getting Started" October 14, 2016.

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