Some people say that the dua اللَّهُمَّ لَكَ صُمْتُ، وَعَلَى رِزْقِكَ أَفْطَرْتُ is not proven from Prophet Muhammad ﷺ and the hadith which has these words is weak (Daeef).
Below is the Daleel and Analysis on this issue:
حَدَّثَنَا ابْنُ فُضَيْلٍ، حَدَّثَنَا حُصَيْنٌ، عَنْ أَبِي زُهْرَةَ، قَالَ: كَانَ النَّبِيُّ صَلَّى اللَّهُ عَلَيْهِ وَسَلَّمَ إِذَا صَامَ، ثُمَّ أَفْطَرَ يَقُولُ: «اللَّهُمَّ لَكَ صُمْتُ، وَعَلَى رِزْقِكَ أَفْطَرْتُ»
In the above hadith, it is mentioned by Abu Zohra Rh. that when it s time for Iftaar, they recited: اللَّهُمَّ لَكَ صُمْتُ، وَعَلَى رِزْقِكَ
(Ad- Duaa Liz Zabbai : Hadith No 66)
NOTE: This narration is Mursal and according to the majority of Muhadiseen it can be used as a Proof or Evidence.
A quick view on what the Fuqaha and Muhadiseen have said about Mursal Ahadith is mentioned below:
a. Imam Ibn Jareer Rh. says that all Tabien agree that Mursal ahadith are agreeable and till 2nd century no one has opposed it. (Tadreeb ur Raavi : Page 104)
b. Imam Suyuti Rh. says that Imam Malik Rh. , Imam Abu hanifa Rh. and Imam Ahmed Rh. have all said that Mursal traditions are Saheeh (Correct). (Tadreeb ur Raavi : Page 103)
c. Imam Nawawi Rh. also states that Imam Malik Rh. and Imam Abu Hanifa Rh. both see Mursal traditions as Saheeh (Correct) (Taqreeb Lin Nawawi : Page 55)
Now lets go back to our main topic of Dua before Iftar.
Even Imam Abu Dawud Rh. Al Mutawaffa 275 Hij. copies this narration (hadith) in his Sunan and have remained silent on it. (Sunan e Abi Dawud : Hadith No 2358)
Remaining silent on a narration (Hadith) is a sign of its credibility and its daleel. (Fataawa Hasaariya : Volume 6 : Page 14)
We also find some evidences of this hadith and they are all mentioned below:
1 – Hazrat Ali Rdh. says that Prophet Muhammad ﷺ use to recite this when its time for Iftar:
اللَّهُمَّ لَكَ صَمْتُا وَعَلَى رِزْقِكَ أَفْطَرْتُا
(Musnad e Zaid bin Ali : Page 183 , HASAN)
2 – Hadhrat Anas Rdh. says that Prophet Muhammad ﷺ when use to have iftar, would recite:
بِسْمِ اللَّهِ اللَّهُمَّ , لَكَ صُمْتُ , وَعَلَى رِزْقِكَ أَفْطَرْتُ
(Mu-ajjam ul Ausat Lit Tabraani : Volume 7 : Page 298, Daeef)
3 – Hazrat Ibn Abbas Rdh. says that Prophet Muhammad ﷺ would recite this when its iftar :
اللَّهُمَّ لَكَ صُمْنَا، وَعَلَى رِزْقِكَ أَفْطَرْنَا
(Sunan e Darqutni : Hadith No 2280, Daeef)
4 – Hadhrat Antarah bin Abdur Rehman Rdh. [there is a Ikhtilaaf on him being a Sahabi (Companion)] also states the same. (Atraaful Gharaaib Lid Darqutni : Volume 3 : Page 312, Daeef)
Sheikh Rayees Nadwi writes in his book : Mursal ahadith are acceptable among the Hanafi and Maliki jurists while other jurists accept it under some conditions. The conditions include that it should be supportive through other narrations, even if they are Daef.
(Namaz e Janaaza aur Uske Masaail : Page 46)
So we learn that if a Mursal Hadith is supported by other ahadith, even if they are Daeef - it becomes credible and agreeable to be followed.
(Namaz e Janaaza aur Uske Masaail : Page 118)
Note 1 :
In this Dua وعليك توكلت words are also mentioned in the narration quoted by Hadhrat Anas Rdh., and he says: Prophet Muhammad ﷺ said - recite this Dua when its time for iftar:
اللهم لك صمت، وعلى رزقك أفطرت، وعليك توكلت
(Al Afraad Lid Darqutni : Volume 1 : Page 102, Daeef)
In another narration which is through Hadhrat Ali Rdh. : Prophet Muhammad ﷺ said to recite this dua after Iftar:
اللَّهُمَّ لَكَ صُمْتُ وَعَلَيْكَ تَوَكَّلْتُ، وَعَلَى رِزْقِكَ أَفْطَرْتُ
(Musnad Al Haaris : Hadith No 469, Daeef)
So we learn that the words وعليك توكلت are also present in Daef hadiths and the Scholars agree that in matters of Fazaail, Daef ahadiths can be quoted and can be acted upon it.
(Al Majmu Lin Nawawi : Volume 2 : Page 94)
Hence the addition of the words وعليك توكلت is also correct.
The conclusion of the above is that it is better to jurst recite the following during the time of Iftar:
اللَّهُمَّ لَكَ صُمْتُ، وَعَلَى رِزْقِكَ أَفْطَرْتُ
But if someone recites
‘اللهم لك صمت وبك امنت وعليك توكلت وعلى رزقك أفطرت
then it is also acceptable and Muhaddis Mulla Ali Qari Rh. also says the same in its favor.
(Mirqaat : Volume 4 : Page 489)