Muhammad bin Yahya bin Habban said: Two men from the tribe of Ashja' informed me that Muhammad bin Maslamah al-Ansari (may Allah be pleased with him) used to come to them as a collector, and he would say to the owner of the wealth: Bring out the zakah of your wealth. Whatever sheep they brought to him in zakah that fulfilled his due, he would accept it. Malik (may Allah have mercy on him) said: The Sunnah is that people should not be put to hardship in collecting zakah, and that whatever they pay in zakah should be accepted from them. The Shaykh (may Allah have mercy on him) said: This is when the zakah fully meets what is obligatory upon him, as has been stated in the hadith of Muhammad bin Maslamah (may Allah be pleased with him).
Hadith Referenceالسنن الكبرى للبيهقي / كتاب الزكاة / 7309