Luke's version of the Beatitudes are quite different from Matthew's. And, unlike Matthew's, they are more directly concerned with the materially, and not just spiritually, poor. They turn our common values upside down - blessed are the poor, the hungry, the sad, the persecuted and woe to the rich, the well-fed, the self-content, the well-spoken of.
Can Jesus be serious? We need to realise He is speaking of the situation in the Kingdom that He wishes to inaugurate on earth - a world where poverty, hunger and persecution come to an end, in a world where everyone is committed to attending to the needs of others and not selfishly looking after themselves. It is not good news for those self-focused people who amass material wealth at the expense of others, who indulge in excessive consumption of the world's goods, who live lives centred on personal hedonism and pleasure, and who feed off the envy and adulation of the masses.
There is really no place for such people in the Kingdom. To enter fully into the Kingdom they have to unload all these concerns and obsessions and let go. Instead of focusing on what they can get; they will focus on what they can share of what they have. The ultimate goal is that all, without exception, be blessed.
Rejoice on that day and leap for joy, for surely your reward is great in heaven.