3097 -  ‘Aa’ishah(may Allah be pleased with her) narrated:
Allah's Messenger ﷺ died, and there was nothing in my house that a living being could eat, except some barley lying on a shelf. So, I ate of it for a long period and measured it, and (after a short period) it was consumed.
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Commentary :
The Prophet ﷺ used to invoke Allah, Exalted is He, to bless him and his family with enough sustenance that would spare them the need to ask others for financial help. His wives and household members (may Allah be pleased with them) were content (with their modest shares of worldly pleasures and properties) and endured the strained living conditions, aspiring to the rewards of Allah, Exalted is He, and the everlasting bliss in Paradise.
In this hadeeth, the Mother of the Believers ‘Aa’ishah(may Allah be pleased with her) stated that when the Prophet ﷺ died, there was nothing in her house that a living being could eat, except some barley lying on a shelf. So, she (may Allah be pleased with her) ate of it for a lengthy period and it was not consumed. She (may Allah be pleased with her) measured it, and (after a brief period) it was consumed. This means that she (may Allah be pleased with her) used to eat of this small quantity of barley for an extended period of time and it was not measured. When she (may Allah be pleased with her) measured it and knew its exact weight and amount, it was no longer so blessed and was consumed (after a short period). Not knowing the exact measure of the foodstuff made it blessed; each day she would think that the barley would be consumed, as it seemed a small quantity, and this is why it lasted for longer before being ultimately consumed. It is also possible that this was related to the blessing of the Prophet ﷺ, and when she measured it, such blessing ceased. It was recorded in Saheeh Al-Bukhaaree and Saheeh Muslim on the authority of Asmaa’ bintAboo Bakr (may Allah be pleased with her) that the Prophet ﷺ said: “Spend in charity and do not calculate, (for) Allah would calculate in your case; and do not hoard, otherwise Allah would be withholding from you.” It means, ‘Do not measure and meticulously calculate what you spend in charity, lest Allah, Exalted is He, do the same to you (i.e., in terms of reward and blessing). When one relies on the blessing of Allah, Exalted is He, refrains from measuring and meticulously calculating his foodstuff, and eats thereof until it is consumed, he would avail himself of the blessings bestowed by Allah, Exalted is He.
The hadeeth urges Muslims to give precedence to the enjoined reliance on Allah, Exalted is He, (over the reliance on the worldly and material causes) in all matters.
It is deduced from the hadeeth that when a person measures and meticulously calculates the quantity of foodstuff, closely monitoring the consumed or remaining amount, it becomes unblessed. .