Tell the fool to read Muwatta Imam Malik (RA) and the read the Fatwa of Shaykh Uthaymeen (RA) who says:
ثم إن الرَّسولَ عليه الصَّلاةُ والسَّلامُ علَّمه أمَّته ، حتى إنه كان يُعَلِّم ابنَ مسعود ، وكَفُّه بين كفَّيه من أجل أن يستحضر هذا اللَّفظَ ، وكان يُعلِّمُهم إيَّاه كما يُعلِّمُهم السُّورة من القرآن ، وهو يعلَم أنه سيموت ؛ لأن الله قال له : ( إنك ميت وإنهم ميتون ) الزمر / 30 ، ولم يقلْ : بعد موتي قولوا : السَّلامُ على النَّبيِّ ، بل عَلَّمَهم التشهُّدَ كما يُعلِّمُهم السُّورةَ من القرآن بلفظها ، ولذلك لا يُعَوَّلُ على اجتهاد ابن مسعود ، بل يُقال : " السَّلامُ عليك أيُّها النبيُّ " .
" الشرح الممتع " ( 3 / 150 ، 151 ) .
Moreover the Messenger (peace and blessings of Allaah be upon him) taught it to his ummah, and he even taught it to Ibn Mas’ood, holding his hand between his own, so that he would remember this wording. He used to teach it to them as he used to teach them a soorah from the Qur’aan. And he knew that he was going to die, because Allaah said to him (interpretation of the meaning):
“Verily, you (O Muhammad) will die, and verily, they (too) will die”
[al-Zumar 39:30]
But he did not say: after I die, say “al-salaamu ‘ala al-nabi (peace be upon the Prophet)”, rather he taught them the tashahhud as he used to teach them a soorah of the Qur’aan, with this wording. Hence we should not rely on the ijtihaad of Ibn Mas’ood, rather we should say, “al-salaamu ‘alayka ayyhu’l-nabiyyu (peace be upon you, O Prophet)”.
Al-Sharh al-Mumti’, 3/150-151
