Levi's descendants are now the ones who receive a tenth from people. We could even say that when Abraham gave Melchizedek a tenth, Levi also gave him a tenth.
Every year you are to give ten per cent of your harvest to the LORD. But every third year, this ten per cent must be given to the poor who live in your town, including Levites, foreigners, orphans, and widows. That way, they will have enough to eat.