say to them call upon him as allah or call upon him as alrahman call him by whichever name you will all his names are beautiful. neither offer your prayer in too loud a voice nor in a voice too low but follow a middle course.
قل ادعوا الله أو ادعوا الرحمن أيا ما تدعوا فله الأسماء الحسنى ولا تجهر بصلاتك ولا تخافت بها وابتغ بين ذلك سبيلا