This commentary explains ayahs 12:37–38 together.
Yusuf calls His Jail Mates to Tawhid even before He interprets Their Dreams
Yusuf, peace be upon him, told the two men that he has knowledge in the interpretation of whatever they saw in their dream, and that he will tell them about the interpretation of the dreams before they become a reality. This is why he said,
لاَ يَأْتِيكُمَا طَعَامٌ تُرْزَقَانِهِ إِلاَّ نَبَّأْتُكُمَا بِتَأْوِيلِهِ
(No food will come to you as your provision, but I will inform you of its interpretation) Mujahid commented,
لاَ يَأْتِيكُمَا طَعَامٌ تُرْزَقَانِهِ
(No food will come to you as your provision,) this day,
إِلاَّ نَبَّأْتُكُمَا بِتَأْوِيلِهِ قَبْلَ أَن يَأْتِيَكُمَا
(but I will inform you of its interpretation before it comes.) As-Suddi said similarly. Yusuf said that, this knowledge is from Allah Who taught it to me, because I shunned the religion of those who disbelieve in Him and the Last Day, who neither hope for Allah's reward nor fear His punishment on the Day of Return,
وَاتَّبَعْتُ مِلَّةَ ءَابَآءِي إِبْرَهِيمَ وَإِسْحَـقَ وَيَعْقُوبَ
(And I have followed the religion of my fathers, - Ibrahim, Ishaq and Ya`qub) Yusuf said, `I have avoided the way of disbelief and polytheism, and followed the way of these honorable Messengers,' may Allah's peace and blessings be on them. This, indeed, is the way of he who seeks the path of guidance and follows the way of the Messengers, all the while shunning the path of deviation. It is he whose heart Allah will guide, teaching him what he did not know beforehand. It is he whom Allah will make an Imam who is imitated in the way of righteousness, and a caller to the path of goodness. Yusuf said next,
مَا كَانَ لَنَآ أَن نُّشْرِكَ بِاللَّهِ مِن شَىْءٍ ذلِكَ مِن فَضْلِ اللَّهِ عَلَيْنَا وَعَلَى النَّاسِ
(and never could we attribute any partners whatsoever to Allah. This is from the grace of Allah to us and to mankind,) this Tawhid -Monotheism-, affirming that there is no deity worthy of worship except Allah alone without partners,
مِن فَضْلِ اللَّهِ عَلَيْنَا
(is from the grace of Allah to us), He has revealed it to us and ordained it on us,
وَعَلَى النَّاسِ
(and to mankind,), to whom He has sent us as callers to Tawhid,
وَلَـكِنَّ أَكْثَرَ النَّاسِ لاَ يَشْكُرُونَ
(but most men thank not.) they do not admit Allah's favor and blessing of sending the Messengers to them, but rather,
بَدَّلُواْ نِعْمَتَ اللَّهِ كُفْرًا وَأَحَلُّواْ قَوْمَهُمْ دَارَ الْبَوَارِ
(Have changed the blessings of Allah into disbelief, and caused their people to dwell in the house of destruction.) 14:28