He who withholds but a pennyworth of worldly goods from his neighbor, knowing him to be in need of it, is a robber in the sight of God.

Meister Eckhart (c. 1260-1328?) German theologian, philosopher, mystic [a.k.a. Johannes Eckhart von Hochheim; Eckhart; Eckehart]

Meister Eckhart, Tractate 6, “Sister Katrei” [ed. Pfeiffer (1857), tr. Evans]
    (Source)