Valmiki Ramayana Bala Kanda Sarga 13 Shloka 30

तत: then, प्रीत: pleased, द्विजश्रेष्ठः best among brahmins, तान् सर्वान् addressing all of them, इदम् these words, अब्रवीत् said, कस्य चित् to any one, अवज्ञया with insult, लीलयापि वा or casually, न दातव्यम् should not be gifted, अवज्ञया with contempt, कृतम् done, दातारम् donor, हन्यात् destroys, अत्र in this aspect, संशय: न no doubt.

Then, well pleased, the best among brahmins (Vasishta) said to them all "Nobody should be offered any thing with disregard. Anything given with contempt undoubtedly results in the destruction of the donor."