What does Romans 11:34 mean?

Paul's hymn of praise and adoration for the God who is beyond us continues here. He asks two questions, quoted from Isaiah 40:13, to illustrate just how little God needs from us.

First, who has known the Lord's mind? The answer is so obvious that Paul does not bother to respond. Nobody has ever known God's mind. As beings created by Him, we lack any capacity to fully grasp His thoughts (Isaiah 55:8–9). To assume that we could possibly know anything about God's thinking processes beyond what He has revealed in His Word is foolish arrogance. To recognize His mind as unknowable to us is cause for worship.

The second question is as ridiculous as the first. Who has been God's counselor? Who has God gone to for counselling, or moral support, or for relationship advice? Who has He asked for ideas about creation or the care of His creatures? God doesn't need us to help Him think things through, no matter how eager we sometimes feel to do exactly that. As we begin to understand the difference between His vast mind and our own, the only response that makes sense is to worship Him and accept His decisions as right and true.