Sayyiduna Fadalah bin Ubayd (may Allah be pleased with him) said: "Some people want to turn me away from my religion, and by Allah, I hope to remain upon it until I die. Anything that is sold for gold or silver, in it is the one-fifth of Allah and the share of the Muslims."
Hadith Referenceالسنن الكبرى للبيهقي / كتاب السير / 18001