Ramayana
अर्थिनामुपपन्नानां पूर्वं चाप्युपकारिणाम् । आशां संश्रुत्य यो हन्ति स लोके पुरुषाधमः ॥ ४-३०-७१
'He who, having promised to his friend to grant his desire and who, having been obliged, fails to implement the promise, is the lowest on earth. ॥ 4-30-71॥
english translation
arthinAmupapannAnAM pUrvaM cApyupakAriNAm । AzAM saMzrutya yo hanti sa loke puruSAdhamaH ॥ 4-30-71
hk transliteration by Sanscript