Sayyiduna Abdullah bin Umar (may Allah be pleased with them both) narrates from the Messenger of Allah (peace and blessings be upon him) that he said: "Whoever fasts on Wednesday, Thursday and Friday and gives in charity whatever he has, little or much, Allah will forgive his sins, and he will become as free of his sins as on the day his mother gave birth to him."
Hadith Referenceالسنن الكبرى للبيهقي / كتاب الصيام / 8449