What does Psalm 34:10 mean?

Having grown up in the outdoors, as a shepherd, David would have been acquainted with lions. We know from his testimony in 1 Samuel 17:34–35 that he killed at least one lion that was attacking his sheep. He probably encountered hungry lions more than once. David knew even strong, young lions could go hungry. In contrast to those animals, he was confident that those who seek the Lord lack nothing good for them.

Of course, this does not mean that we will always get what we "want" from God. Or, even that what we think are "needs" will be met. What we truly "need" is always understood in the context of God's will for us and our lives. Everyone who belongs to the Lord encounters adversity occasionally, but He uses that adversity for our good. The apostle Paul wrote that earthly sufferings cannot compare to the glory of eternity (Romans 8:18). Further, he assured us in Romans 8:28 that "for those who love God all things work together for good, for those who are called according to his purpose."

Paul further identified this purpose (Romans 8:29–30) as being conformed to the image of God's Son. God has not promised an affluent lifestyle to those who seek Him (John 16:33). What He has promised is that we will never lack what is in our best interest. He has not promised to meet our wants, or to satisfy our expectations, but He has promised to meet all our needs.