Shiva Purana
इच्छावतः प्रदानं च संपूर्णफलदं विदुः । यत्प्रश्नानंतरं दत्तं तदर्धं फलदं विदुः २१ ।
A charitable gift given to a needy person yields the utmost benefit. If it is given after entreaties it yields only half the benefit.
english translation
icchAvataH pradAnaM ca saMpUrNaphaladaM viduH । yatpraznAnaMtaraM dattaM tadardhaM phaladaM viduH 21 ।
hk transliteration by Sanscript