Bhagavad Gita · 17.20

दातव्यमिति यद्दानं दीयतेऽनुपकारिणे।देशे काले च पात्रे च तद्दानं सात्त्विकं स्मृतम्॥

dātavyam iti yad dānaṁ dīyate 'nupakāriṇe deśhe kāle cha pātre cha tad dānaṁ sāttvikaṁ smṛitam

Charity given out of duty, to a worthy person, at the right place and time, and to one who cannot give anything in return — that charity is considered to be in the mode of goodness.

— Bhagavad Gita 17.20

Source: Sacred-Texts.com (Sanskrit) + Bhagavad-Gita.io (translations)