Assalamualaikum ustaz. What is the ruling of believing that one’s sustenance will be cut off if a person is late in buying rice after he has run out of it?
Waalaikumussalam wrt. wbt.,
Alhamdulillah, praise and gratitude to Allah SWT for His countless blessings for us all. Praise and salutations to our beloved Prophet Muhammad PBUH, his family, companions, and all those who follow his footsteps until the Final day.
The basic matter in faith that one should believe in is that Allah SWT is the Provider. None can ever give or stop the sustenance of a person except Allah SWT. Allah SWT states:
قُلْ مَن يَرْزُقُكُم مِّنَ السَّمَاوَاتِ وَالْأَرْضِ ۖ قُلِ اللَّـهُ ۖ
Say, “Who provides for you from the heavens and the earth?” Say, “Allah.” 
Al-Razi said: “(This verse) signals that there is nothing that could benefit except by the will of Allah and all of it comes from Allah.” 
Every creation including animals, Allah has set its sustenance. Allah SWT states:
وَمَا مِن دَابَّةٍ فِي الْأَرْضِ إِلَّا عَلَى اللَّـهِ رِزْقُهَا وَيَعْلَمُ مُسْتَقَرَّهَا وَمُسْتَوْدَعَهَا ۚ كُلٌّ فِي كِتَابٍ مُّبِينٍ
“And there is no creature on earth but that upon Allah is its provision, and He knows its place of dwelling and place of storage. All is in a clear register.” 
This verse explains that no creation that has been granted life by Allah that will be left without a guarantee of provision. Ibn Kathir said: “Allah SWT has informed that He is the guarantor of sustenance of all creations including all animals. Small, big, in the sea or on land.” 
Believing that sustenance will be cut off if one is late in buying rice
Such beliefs don’t have any basis or origin in Islam. If what is meant is that there is no longer any food in the house and he may not be able to eat that day, then this is reasonable and accepted as just an expression.
However, if he truly believes that the rice at his house has finished and that if he is late in buying new rice, then sustenance that has been set by Allah will also be late, then this is wrong and one should avoid such belief. The sustenance of Allah is indeed vast compared to just rice. Allah SWT stated in the Quran:
الَّذِي جَعَلَ لَكُمُ الْأَرْضَ فِرَاشًا وَالسَّمَاءَ بِنَاءً وَأَنزَلَ مِنَ السَّمَاءِ مَاءً فَأَخْرَجَ بِهِ مِنَ الثَّمَرَاتِ رِزْقًا لَّكُمْ ۖ فَلَا تَجْعَلُوا لِلَّهِ أَندَادًا وَأَنتُمْ تَعْلَمُونَ
“[He] who made for you the earth a bed [spread out] and the sky a ceiling and sent down from the sky, rain and brought forth thereby fruits as provision for you. So do not attribute to Allah equals while you know [that there is nothing similar to Him].” 
In the arrangement of the 40 hadiths of Imam al-Nawawi it is stated in a hadith of Rasullullah PBUH:
إنَّ أَحَدَكُمْ يُجْمَعُ خَلْقُهُ فِي بَطْنِ أُمِّهِ أَرْبَعِينَ يَوْمًا نُطْفَةً، ثُمَّ يَكُونُ عَلَقَةً مِثْلَ ذَلِكَ، ثُمَّ يَكُونُ مُضْغَةً مِثْلَ ذَلِكَ، ثُمَّ يُرْسَلُ إلَيْهِ الْمَلَكُ فَيَنْفُخُ فِيهِ الرُّوحَ، وَيُؤْمَرُ بِأَرْبَعِ كَلِمَاتٍ: بِكَتْبِ رِزْقِهِ، وَأَجَلِهِ، وَعَمَلِهِ، وَشَقِيٍّ أَمْ سَعِيدٍ؛
“Verily the creation of each one of you is brought together in his mother’s womb for forty days in the form of a nutfah (a drop), then he becomes an alaqah (clot of blood) for a like period, then a mudghah (morsel of flesh) for a like period, then there is sent to him the angel who blows his soul into him and who is commanded with four matters: to write down his rizq (sustenance), his life span, his actions, and whether he will be happy or unhappy (i.e., whether or not he will enter Paradise).” 
In a story narrated by Aisyah R.anha:
دَخَلَ عَلَيَّ النَّبِيُّ صَلَّى اللهُ عَلَيْهِ وَسَلَّمَ ذَاتَ يَوْمٍ فَقَالَ: هَلْ عِنْدَكُمْ شَيْءٌ؟ فَقُلْنَا: لَا، قَالَ: فَإِنِّي إِذَنْ صَائِمٌ. ثُمَّ أَتَانَا يَوْمًا آخَرَ فَقُلْنَا: يَا رَسُولَ اللهِ، أُهْدِيَ لَنَا حَيْسٌ فَقَالَ: أَرِينِيهِ، فَلَقَدْ أَصْبَحْتُ صَائِمًا، فَأَكَلَ
The Prophet came to visit me one day and asked if I had anything [to eat]. When I said I had nothing he replied, “Then I shall observe a fast.” When he came to me another day and I told him I had been given a present of some hais (A mixture of dates and clarified butter) he said, “Show me it, for I began the day fasting.” Then he ate. 
This story shows that zuhud displayed the feeling of the sufficiency of the Rasullullah PBUH. Nothing describes that if one doesn’t buy food then it means that Allah’s sustenance will be cut off from him.
Thus, we should avoid the superstition that one’s sustenance will be cut off if one is late in buying rice for it is inappropriate and contradicts the concept of sustenance and fate in Islam.
 Surah Saba’: 24
 See Mafatih al-Ghaib, 25/205
 Surah Hud: 6
 See Tafsir al-Quran al-‘Azim, 3/305
 Surah al-Baqarah: 22
 Narrated by al-Bukhari (3308) and Muslim (2643)
 Narrated by Muslim (1154)