What does Romans 11:33 mean?

Paul has just concluded a long and complicated discussion of God's unique relationship with Israel as a nation and with her people as individuals. He has compared and contrasted God's actions toward Israel with His actions toward the Gentiles. He wrapped it up in the previous verse by declaring, in essence, that both groups have lived in disobedience and that God will show mercy to people from both groups in response to their faith in Christ.

Now Paul delivers a poem, structured much like a hymn, expressing his profound reaction both to God's ways and to His mercy to sinful human beings.

Paul starts by marveling at the depth of three of God's characteristics. He is stunningly rich or wealthy. Earlier in Romans, Paul has written about the riches of God's kindness and patience (Romans 2:4), the riches of His glory (Romans 9:23), and His riches—of mercy—for the world (Romans 11:12). In each case, God's riches are described as graciously shared and never-ending.

Next, Paul is awed by the depth of God's wisdom, likely in the expression of His love and power in making mercy available to all people through faith in Christ. This is followed by God's deep knowledge, perhaps a reference to His "foreknowledge" of all who will come to Him through faith in Christ (Romans 8:29; 11:2).

Paul's next two lines begins with "how." How unsearchable or unfathomable are God's judgments, Paul wonders. In other words, human beings simply lack the capacity to understand why God decides what He does. God's ways are said to be inscrutable, like a code we can't break.

One reason God retains the right to do as He will when it comes to showing mercy or not to human beings is that we do not have the capacity to understand His choices. His thoughts, His ways, His decisions are beyond us. We are left to simply yield to Him and to worship Him.