Who did God grieve with for 40 years in Hebrews 3:16?
According to Hebrews 3:16, God was grieved for 40 years with the Israelites who came out of Egypt by Moses, specifically those who heard, provoked, and sinned, whose carcasses fell in the wilderness. They were the generation that murmured in unbelief after the spies' report.
Les explains that Hebrews 3:16 refers to the Israelites who came out of Egypt under Moses. They provoked God by their unbelief after the spies returned from the land with a bad report, saying the people were giants and they were as grasshoppers. They moaned and groaned all night, which was another Tisha B'Av, Israel's great day of mourning. Their problem was unbelief. Because of this, God was grieved with them for 40 years, and their carcasses fell in the wilderness. Les also connects this to the golden calf incident, when Moses was on Mount Sinai 30 or 40 days and the people asked Aaron for an idol, and Aaron produced the golden calf.
For some, when they had heard, did provoke: howbeit not all that came out of Egypt by Moses.