[Machine] I heard my Khalil Abu Al-Qasim (Peace be upon him) say that for voluntary fasting, it is recommended to fast until halfway through the day. And Ali ibn Ahmad ibn Abdan informed us that Ahmad ibn Ubayd Al-Saffar told us that Muhammad ibn Al-Faraj Al-Azraq mentioned it with its chain of narrators, similar to Ibrahim ibn Muzahim and Sari' ibn Nabhana, who are both unknown.  

سَمِعْتُ خَلِيلِي أَبَا الْقَاسِمِ ﷺ يَقُولُ الصَّائِمُ فِي التَّطَوُّعِ بِالْخِيَارِ إِلَى نِصْفِ النَّهَارِ 8359 وَأَخْبَرَنَا عَلِيُّ بْنُ أَحْمَدَ بْنِ عَبْدَانَ أنبأ أَحْمَدُ بْنُ عُبَيْدٍ الصَّفَّارُ ثنا مُحَمَّدُ بْنُ الْفَرَجِ الْأَزْرَقُ فَذَكَرَهُ بِإِسْنَادِهِ مِثْلَهُ إِبْرَاهِيمُ بْنُ مُزَاحِمٍ وَسَرِيعُ بْنُ نَبْهَانَ مَجْهُوَلَانِ