How do we reconcile the message of Ezekiel 18 which says a son is not punished for his father's sins, with Exodus 34:7 which speaks of God "punishing the children for the sin of the fathers to the third and fourth generation"?
Excellent question. At the surface level this appears to be a contradiction. God spoke through both Ezekiel and Jeremiah clarifying to the people of Israel that a father's sins do not affect how the son is treated--good or bad. The key statement of Ezekiel 18 is: "The soul who sins is the one who will die." 18:4b (NIV)
So how does that compare with God's statement in Exodus 34:7 where God says: "...he punishes the children and their children for the sin of the fathers to the third and fourth generation." Exodus 34:7 (NIV)??
Actually this comment is an abbreviated version of a similar one the Lord made to Israel in the Ten Commandments. In that passage the Lord said:
You shall not bow down to them or worship them; for I, the LORD your God, am a jealous God, punishing the children for the sin of the fathers to the third and fourth generation of those who hate me, but showing love to a thousand [generations] of those who love me and keep my commandments. Exodus 20:5-6 (NIV)
There are some vitally important words here that many people miss. God says He will punish the children for the sins of the father to the third and fourth generation OF THOSE WHO HATE ME." In other words, God is saying that His visitation of punishment upon the children is because they are committing the same sins as their fathers. There has been no repentance and there is no change of heart.
Ezekiel 18 elaborates on God's justice and judgment by explaining that if a father refuses to walk before the Lord in any kind of righteousness and stubbornly refuses to repent of his ways, he will die for his sin. But if that very man has a son who turns to the Lord and decides to walk uprightly before God, that child will suffer no disadvantage due to his father's sinful attitude. God actually rebuked the Jews for believing otherwise. (A complete reading of Ezekiel 18 will reveal this.)