Rashi on Deuteronomy 15:4/רש"י על דברים ט״ו:ד׳

1אפס כי לא יהיה בך אביון HOWBEIT THERE SHALL BE NO NEEDY AMONG YOU — But further on (v. 11) it states, “For the needy shall never cease out of the land”! But the explanation is: When you do the will of the Omnipresent the needy will be amongst the others and not amongst you, if, however, you do not the will of the Omnipresent, the needy will be amongst you (Sifrei Devarim 114:1).

2אביון denotes a person who is more destitute than an עני. The term אביון (from the root אבה “to long for”, “to desire”; cf. Rashi on Exodus 23:6) denotes one who longs for everything (because he lacks everything) (Leviticus Rabbah 34:6).