Sayyiduna Abu Hurayrah (may Allah be pleased with him) said: When the Prophet (peace and blessings be upon him) passed away and Abu Bakr (may Allah be pleased with him) was made caliph, some of the Arabs refused to pay zakah. Umar (may Allah be pleased with him) said: O Abu Bakr! How can you fight these people, when the Prophet (peace and blessings be upon him) said: "I have been commanded to fight people until they say 'La ilaha illallah' (there is no god but Allah); whoever says 'La ilaha illallah' (there is no god but Allah) has protected his wealth and his life from me, except by its right, and his reckoning is with Allah Almighty"? Abu Bakr (may Allah be pleased with him) said: By Allah! I will certainly fight whoever makes a distinction between prayer and zakah, for zakah is the right due on wealth. By Allah! If they withhold from me even a young she-goat which they used to give in the time of the Prophet (peace and blessings be upon him), I will fight them over it. Umar (may Allah be pleased with him) said: By Allah! I saw that Allah had opened the chest of Abu Bakr (may Allah be pleased with him) to fighting, and I knew that it was the truth.
Hadith Referenceالسنن الكبرى للبيهقي / كتاب قسم الصدقات / 13115
It is narrated from Imam Layth (may Allah have mercy on him) like the previous hadith, except that in it the word 'iqalan (a hobbling cord) occurs in place of 'anaqan (a young she-goat).
Hadith Referenceالسنن الكبرى للبيهقي / كتاب قسم الصدقات / 13116
Imam al-Kisa'i (may Allah have mercy on him) said: 'Iqal' refers to the sadaqah (zakah) of one year. It is narrated from al-Asma'i (may Allah have mercy on him) that it is said: So-and-so was sent to collect the 'iqal' of such-and-such tribe; this is said when he was sent to collect their zakah.
Hadith Referenceالسنن الكبرى للبيهقي / كتاب قسم الصدقات / 13117
Hizam bin Hisham bin Hubaysh al-Khuza'i heard his father say: I saw Sayyiduna Umar bin al-Khattab (may Allah be pleased with him) with his waist tied firmly with a cord, while he was working with some of the sadaqah camels. Mansur said: As I remember, he was selling them by auction; whenever he sold a camel from them, he tied its cord around his waist, then he gave them away in charity, that is, those cords.
Hadith Referenceالسنن الكبرى للبيهقي / كتاب قسم الصدقات / 13118
It is narrated from Sayyiduna Abu Hurayrah (may Allah be pleased with him) that the Prophet (peace and blessings be upon him) said: "I have been commanded to fight people until they affirm 'La ilaha illallah' (There is no god but Allah), establish the prayer and begin paying zakah. When they do this, their blood and their wealth become forbidden to me, but their matter rests with Allah Almighty."
Hadith Referenceالسنن الكبرى للبيهقي / كتاب قسم الصدقات / 13119
It is narrated from Sayyiduna Abu Hurayrah (may Allah be pleased with him) that the Prophet (peace and blessings be upon him) said: "I have been commanded to fight people until they affirm the kalimah, begin performing the prayer and start paying zakah. When they do this, they will have protected their wealth and their blood from me, except by its right, and their reckoning rests with Allah."
Hadith Referenceالسنن الكبرى للبيهقي / كتاب قسم الصدقات / 13120