Thanks, that works fine:
\definefont[arabicamiri][file:amiri-regular.ttf*arabic at 15pt] \definefont[arabicuth][file:UthmanicHafs1Ver09.ttf*arabic at 17pt] \def\eoa#1{#1\char"06DD} \starttext \setupalign[r2l] \arabicuth لأَفَبِهَـٰذَا ٱلْحَدِيثِ أَنتُم مُّدْهِنُونَ ﴿٨١﴾\eoa \stoptext
Now I could locate the error in ConText better, see this code and the mistake, which occurs: \definefont[arabicuth][file:UthmanicHafs1Ver09.ttf*arabic at 17pt] \define[1]\eoa{#1\char"06DD} \starttext \setupalign[r2l] \arabicuth إِنَّ ٱلَّذِينَ كَفَرُوا سَوَآءٌ عَلَيْهِمْ ءَأَنذَرْتَهُمْ أَمْ لَمْ تُنذِرْهُمْ لَا يُؤْمِنُونَ ﴿٦﴾\blank إِنَّ ٱلَّذِينَ كَفَرُوا سَوَآءٌ عَلَيْهِمْ ءَأَنذَرْتَهُمْ أَمْ لَمْ تُنذِرْهُمْ لَا يُؤْمِنُونَ ﴿٦٦﴾ \stoptext (I have attached the compiled PDF). The first aya, with a single one-digit number is not regonized correctly, but the second is (with a two-digit-number). Why? Huseyin