A short answer by: Ash Shaykh Abu Amr Al Hajooree حفظه الله
“It has become widespread amongst the people that a man supplicates for his brother and says
“May Allah reward you In sha Allah”
“May Allah bless you In sha Allah”
“May Allah make it easy for you In sha Allah”
“May Allah cure you In sha Allah”
Or similar to these (supplications)
And this is Haram (prohibited).
This is Haram and not permissible, that you say In shaa Allah. Rather, you say “May Allah reward you”, “May Allah cure you”, “May Allah give you”.
Due to that which comes in The Two Saheehs (Al Bukhari and Muslim), from the narration of Abu Huraira and Anas May Allah be pleased with both of them that the prophet صلى الله عليه و سلم said:
”None of you should say: ‘O Allah! Forgive me if You wish,’ or ‘Bestow Your Mercy on me if You wish,’ or ‘Provide me with means of subsistence if You wish,’ but he should be firm in his request, for Allah does what He wills and nobody can force Him (to do anything)
Thus, your statement Oh Allah gives me if you want, then Allah Aza Wa Jal is never forced, he isn’t incapable, nor weak and you are not able to be self-sufficient from Allah. Thus be firm in your request. Make constant supplications, supplicate with good, supplicate to Allah that he give you Firdaus Al A’alaa (the highest part of paradise) supplicate to Allah that he repel evil from you, supplicate to Allah for good in this world and the hereafter, and be firm in your request.
This action of saying In sha Allah (if Allah wills) in supplications is a mistake, rather it is prohibited.
As for saying In sha Allah in regards to future matters then it is obligatory. You say, for example, tomorrow I will go to Khartoum in sha Allah. It is obligatory that you say In sha Allah in this situation, due to the statement of Allah Aza Wa Jaal
وَلَا تَقُولَنَّ لِشَيْءٍ إِنِّي فَاعِلٌ ذَلِكَ غَداً . إِلَّا أَن يَشَاءَ اللَّهُ
- And never say of anything, “I shall do such and such thing tomorrow.”
- Except (with the saying), “If Allah will!”
Thus if it is in regards to matters of the future, whether that be tomorrow or today, for example you say Oh, So and So tonight I will come to you around Asr, then say In sha Allah.
As an obligation you say In sha Allah In regards to that which will occur in the future.
And (to say In sha Allah) in regards to matters which have passed then it is an innovation. You saying yesterday I went to the market place In sha Allah, it’s an innovation to say In sha Allah (in this situation). Rather, you should say “I went” because you went and it has already occurred.
As for matters of the future then it is obligatory (to say In sha Allah).
How many matters are these?
In supplications, saying In sha Allah is prohibited. Rather you should supplicate, and if your supplication has transgression in it then don’t make that supplication. As for if it is a legislated supplication then say Oh Allah give me, Oh Allah cure me and don’t say In sha Allah.
In matters connected to the future it is obligatory to say In sha Allah, I will do such and such In sha Allah
And in matters connected to the past then it is an innovation, it is an innovation to say I did such and such In sha Allah.”
Translated by Majid Jawed Al Afghanee عفا الله عنه