Romans 11:33

‘O the depth of the riches both of the wisdom and the knowledge of God! How unsearchable are his judgments, and his ways past tracing out!'

As Paul considers the amazing nature of God's plan, to leave the Jews in unbelief so that the way might be opened to the Gentiles, and then sees how this in turn will result in the Gentiles going to the Jews with the Gospel, he cries out in amazement. How deep are the riches both of the wisdom and knowledge of God. How unsearchable are His judgments, how untraceable are His ways. He may also have had in mind the mystery of election, and indeed the mystery of God's whole way of salvation. For all are a matter of wonder and praise. They defy human comprehension, and must therefore be accepted by faith..