18 So Samuel told him everything and did not hide anything from him. Eli responded, "He is the Lord. He will do what He thinks is good." (1 Sam. 3:18)
The night before Samuel had received a message from God telling him what God was going to do to Eli and his family for defiling God's temple. The verse above is Eli's response to that message.
At first glance the response seems strange. Here Eli had been told that God was going to destroy his house forever and nothing could stop it. Eli's response gives us a glimpse of a man who, after living in sin and allowing his sons to live in sin, for so long is not capable of repentance. Compare that to David's response when confronted with his sin of adultery (2Sam. 12:13). We see, here, a contrast between repentance and resignation. Eli's response was not an acknowledgement of God's sovereignty; it was a resignation to his fate. It was also his last chance to choose God over sin.
In both cases God's judgment was pronounced against believers who had sinned. Each sinner responded differently to that pronouncement. And God's judgment was carried out against each of them. God's punishment of David humbled him and was turned into suffering for blessing. Because of it we now have certain Psalms and Proverbs and Israel as a nation received Salomon as king. God's punishment of Eli resulted in the death of Eli and his sons and Israel's loss of the Ark of the Covenant in battle.
Two different men each facing the sin unto death, each responded differently. One's response turned cursing into blessing, the other's response led to judgment and death. Both outcomes did not happen overnight, it took time for the results of sin to work its way out. In one case the discipline intensified, in the other case discipline was not intensified, but the natural results of sin had to run its course. In other words it was self-induced misery, a reaping of what was sowed. God, who is faithful, turned that misery into blessing and David grew. Not only was he blessed but generations after him were blessed because of his repentance.
