Do you know who is poor?
Abu Huraira (Radi Allah Anhu) reported Allah's Messenger (sal-allahu-alleihi-wasallam) as saying:
"Do you know who is poor?"
They (the Companions of the Holy Prophet) said: A poor man amongst us is one who has neither dirham with him nor wealth. He (sal-allahu-alleihi-wasallam) said:
"The poor of my Umma would be he who would come on the Day of Resurrecton with prayers and fasts and Zakat but (he would find himself bankrupt on that day as he would have exhausted his funds of virtues) since he hurled abuses upon others, brought calumny against others and unlawfully consumed the wealth of others and shed the blood of others and beat others, and his virtues would be credited to the account of one (who suffered at his hand). And if his good deeds fall short to clear the account, then his sins would be entered in (his account) and he would be thrown in the Hell-Fire."
Source: Sahih Muslim Book 46, Hadith 6744
http://www.sunnah.com/urn/262510