Reward for fasting is far greater than other good deeds
Every (good) deed of the son of Adam would be multiplied, a good deed receiving a tenfold to seven hundredfold reward. Allah, the Exalted and Majestic, has said: With the exception of fasting, for it is done for Me and I will give a reward for it, for one abandons his passion and food for My sake.
There are two occasions of joy for one who fasts, joy when he breaks it, and joy when he meets his Lord, and the breath (of an observer of fast) is sweeter to Allah than the fragrance of musk.
قَالَ رَسُولُ اللَّهِ ﷺ: «كُلُّ عَمَلِ ابْنِ آدَمَ يُضَاعَفُ الْحَسَنَةُ عَشْرُ أَمْثَالِهَا إِلَى سَبْعِمِائَةِ ضِعْفٍ۔ قَالَ اللَّهُ ﷻ: إِلاَّ الصَّوْمَ: فَإِنَّهُ لِي وَأَنَا أَجْزِي بِهِ: يَدَعُ شَهْوَتَهُ، وَطَعَامَهُ مِنْ أَجْلِي۔»
«لِلصَّائِمِ فَرْحَتَانِ فَرْحَةٌ عِنْدَ فِطْرِهِ وَفَرْحَةٌ عِنْدَ لِقَاءِ رَبِّهِ؛ وَلَخُلُوفُ فِيهِ أَطْيَبُ عِنْدَ اللَّهِ مِنْ رِيحِ الْمِسْكِ۔»