"Blessed are the poor in spirit, For theirs is the kingdom of heaven.” Matthew 5:3
Jewish tradition in Jesus’ day said the opposite. They believed that material prosperity was a sure-fire sign of God’s approval and blessing. And to be fair, many today agree. But is it true? Not at all. While God does bless His people, His blessings are frequently not in the form of material prosperity. If we could give only one example, Jesus would do nicely. He had nothing:
Luke 9:58 And Jesus said to him, "Foxes have holes and birds of the air have nests, but the Son of Man has nowhere to lay His head."
Other examples abound throughout the Bible. From this we can safely conclude that while God does bless the righteous—sometimes with material prosperity—His spiritual blessings are of infinitely greater value. And God’s greatest spiritual blessing is forgiveness of sin and eternal life in Heaven.
Another consideration on this first beatitude is whether Jesus was pronouncing His blessing on the poor in spirit (Matthew 5:3), or on those who are merely poor (as in Luke 6:20). When comparing two parallel passages, we do not weight the verse that says less over the verse that says more. On the contrary, the one that says more frequently provides information necessary to understand the one that says less.
Earthly riches often stand in the way of the wealthy keeping them from acknowledging their need for salvation because the well-to-do often falsely believe their riches will save them. The facts are, being monetarily poor does not guarantee entrance into Heaven, nor does being wealthy axiomatically exclude the rich from Heaven. Numerous examples in scripture support both of these truths.
Therefore, the ones who receive this first blessing in the beatitudes are necessarily poor in spirit regardless of their financial holdings, or lack thereof. The crucial aspect of being poor in spirit is understanding the first point of the gospel: We are all sinners before a Holy God, deserving His just wrath. This is the deepest spiritual poverty.
The good news is that those who realize their spiritual bankruptcy and who receive Christ as Savior and Lord as the only remedy, are made spiritually rich in Christ (2 Corinthians 8:9). These are the ones who receive the kingdom of Heaven.