One of the things the Scriptures are certain about is the responsibility of the people of God to give to the poor. This proverb relates this responsibility in a way that reminds us of the Covenant God made with His people. That covenant often gets a bad reputation for being all about "thou shalt not's." Some think it is a religious buzz-kill - that only tells us what we cannot do. Those who think this way don't realize that there is great deal in the Old Testament Law that speaks of showing compassion and mercy.
Israel was an agrarian society - and as such there were a number of laws that encouraged them to provide for the poor. One of the things that they were told was to only harvest the land once - and not go over it a second time. This was the case with ground crops as well as things like olives and fruit, which are grown on trees. The extra was to be left for the poor. This was one way they gave to the poor - as well as with what were called, "alms" which were specific financial gifts given to care for the poor in society.
God intended for the poor to receive more than just money or food. The church is better equipped morally to help the poor than the government. Governments most often just give out money. Unfortunately this leads to government programs that do more to harm than help the poor. The phrase a hand up - rather than just a hand out comes to mind. Government has made laws that actually award immoral behavior by offering more help to those who have children out of wedlock. These kind of laws may help with the hand out - but they have a bad tendency to lock people into assisted living - rather than help them to eventually become self-reliant and self-sustaining. When the church offers help, they can address immoral behavior in a way that government cannot do. This is the way God desires for the poor to be blessed. He desires for a person's moral choices to be addressed, for often a moral choice leads to a blight on our financial state.
We are told here that the one who gives to the poor will never want. Another proverb states that when we give to the poor, we are lending to the Lord. When we do this - God will be sure to bless us and meet our needs. The second half of this proverb addresses what often happens when the poor are neglected. We do this by closing our eyes to the problem and to their needs. We simply shut our eyes - and then shut our hearts to their plight. This, according to God's Word, will bring to the one who does it, many curses. First there is the curse, which comes from not obeying God's law. That comes with a withdrawal of blessings from God. But there is also a curse that comes from the poor as well. They watch as the rich pamper themselves and ignore their situation. In some situations this reaches a fever pitch and results in revolutions and other violent confrontations. The French Revolution was such a reaction to the abuses of the rich.
God desires for His people - and His church - to care for and love the poor. Because the church has abdicated her role in this - the government has taken over this task. The result of our disobedience in this area is that the government begins to take greater and greater amounts of money to give to the poor. In the end, we are cursed with over-reaching government intrusion into our finances and our lives. We are also cursed with a government that in time realizes it can control the people through ever increasing gifts to the poor. This leads to a curse on those with any level of financial security in society, because the government must increase its revenues to continue the giveaways. This is why God wants His Word to govern such charity - because without something to guide us - our natural sinful tendencies will lead us to use our gifts to secure power or influence.