We say in answer to this question that we do not have clear...
We say in answer to this question that we do not have clear historical evidences about this matter that Khums of all incomes had been taken in the time of Prophet (S) and Ali (a.s.), but this matter makes no problem about this ruling.
Because as we said before, taking and forgiving of this Islamic tax is one of authorities of Islamic government, when government find itself needless or people in trouble it can forgive that but when government has needs and sees the ability of paying in people it can take that, like later Imams who some of them had took Khums and some others had forgave that according to the conditions of people or Bayt Al-Mal.
In the time of Prophet (S) and Ali (a.s.) lots of spoils from battles and also great income from Kharaj lands which their rents had been paid to Bayt Al-Mal had gained by Islamic government; amount of these spoils some times were so much that their Khums could easily solve most of financial problems of Islamic government.
And also sometimes income from Kharaj lands were so much that Bayt Al-Mal had been overflowed by assets and in these conditions there were no need for taking Khums of all incomes and therefore they had forgave it to people practically. At the beginning of Islam when the need of Bayt Al-Mal was so much to resources of income, conditions of Muslims were so unsettled and weak that paying Khums after Zakat was cumbersome for them, and accordingly Khums had not been taken.
But in the time of other Imams (a.s.) when the Khums of spoils of war and also income of Kharaj lands had been taken by usurper caliphs and Imams had not them, and also people had the ability of paying the Khums of all of their incomes, Imams had taken Khums from them. Briefly, not taking Khums in the time of Prophet (S) and Ali (a.s.) from all kinds of income is not he reason for nonexistence of this ruling in the program of rulings of Islam.
Mentioning this point is also necessary that it is understood from some letters of Prophet (S) which we quoted before that he had taken Khums from “Anfal” (dead land, pasturages and streams). And we read in the book “Kanz Al-Ummal[^7]” which if one famous resources of Ahlul Sunnah that he said: ان لکم بطول الارض و سهولها و تلاع الاودیة و ظهورها على ان ترعوا نباتها و تشربوا مائها على ان تؤدّوا الخمس [^1]: Refer to Ahadith of chapter eight from chapters of “What Khums is obligatory in it”, vol.
6 of Wasael Al-Shi’aa. [^2]: Sunan of Beihaghi, vol. 4, page 156. [^3]: Sunan of Beihaghi, vol.