247.If a person earns property through haram means and gives charity, it will not be accepted (by Allah): if he spends it there will be no blessing on it; and if he leaves it behind (at his death) it will be his provision in the Fire. Indeed Allah Ta'ala does not obliterate one bad deed by another bad deed, but He does cancel out a bad deed by a good deed. An unclean thing does not wipe away another unclean thing.
(Ahmad).
(The Lawful and Prohibited in Islam (arb: Al halal wal haram fil Islam) by. Yusuf Al Qaradawi).