first time to say jalla jalaluh or taala is wajib,later to say it is mustahab.we shouldn't write ' (saw) . we should write sallallahu alaiyhi wassallam
many places we see sallallahu 'alaihi wasallam as saw, subhanuhu wa ta'ala as swt etc. i was watching a programme last night where the sunni imam said imam nawawi wrote in sharh sahih muslim vol 1 p 20 that it is mustahab to write with Allah's name jalla jalaluhu etc. ie. we shouldnt just write or say Allah alone. he quoted another imam i think ibn hajar makki or tahtawi that it is makruh tahrimi to write sallallahu 'alaihi wasallam as saw or just arabic saad or sal'am. and i have read about imam suyuti writing that the first person to abbreviate was if i remember rightly lashed or even killed for this. the imam said if you abbreviate to show disrespect then this is obviously kufr.
