Ramayana
अलब्धवरपूर्वेण यत्कृतं राक्षसेन तु । तदेष वरलब्धः स्याद्भक्षयेद्भुवनत्रयम् ॥ 7-10-39 ॥
Such deeds were wrought by this Rakshasa even before he obtained a boon; should he now obtain a boon, he would devour the three worlds.
english translation