Allaah and His Messenger Know Best?

وعن معاذِ بنِ جبلٍ - رضي اللهُ عنه - قال: كُنْتُ رَديفَ النَّبيِّ - صلى الله عليه وسلم - على حمارٍ فَقَالَ لِي: {يَا مُعَاذُ أَتدْرِي مَا حَقُّ الله على الْعِبَادِ، وَمَا حَقُّ الْعِبَادِ عَلى اللهِ}؟ قُلْتُ: اللهُ وَرَسُولُهُ أَعْلَمُ. قَالَ: حَقُّ اللهِ عَلَى العِبَادِ أَنْ يَعبُدُوهُ ولايُشركوا بِهِ شَيْئاً، وَحَقُّ الْعِبَادِ عَلَى اللهِ أَنْ لا يُعَذّبَ مَنْ لا يُشْرِك بِهِ شيْئاً} قُلْتُ: يَا رَسُولَ اللهِ أَفلا أُبَشِّرُ النَّاسَ؟} قَالَ: {لا تُبَشِّرْهُمْ فَيَتَّكِلُوا} أَخرجاه في الصحيحين

Mu’aadh ibn Jabal (radiallaahu ‘anhu) narrated:

"I was with a companion rider of the Prophet (salallaahu ‘alayhe wasallam) on a donkey. The Prophet (salallaahu ‘alayhe wasallam) asked, ‘O Mu’aadh! Do you know Allaah’s right on His servants and the right of His servants on Him?’ I replied, ‘Allaah and His Messenger (salallaahu ‘alayhe wasallam) know best.’ He said, ‘Allaah’s right on His servants is that they must worship Him (only) and must not worship any besides Him. And the servant’s right on Allaah is that He must not punish whoever worships none besides Him.’ I said, ‘O Allaah’s Messenger (salallaahu ‘alayhe wasallam)! Should I not inform the people of this good news?’ He said, ‘Do not inform them of it, lest they should depend on it (absolutely)’.” (Related by Al-Bukhaaree and Muslim)1

Shaykh Saalih Al-Fawzaan (hafidhahullaah) comments:

أنَّ من سُئِلَ عَمَّا لا يعلمُ ينبغي له أن يقولَ: اللهُ أعلمُ

Whoever is questioned about what he does not know should say: ‘Allaah knows best.’

Ustaadh Moosaa Richardson (hafidahullaah) elaborates:

It is appropriate for someone who is asked about knowledge he does not know that he says: ‘Allaahu a’lam’ (Allaah knows best). Today, when people do not know something they say: ‘Allaahu wa rasuulluhu a’lam’ (Allaah and His Messenger know best). These people claim that this is the way of the companions and it has the approval of the Messenger (salallaahu ‘alayhe wasallam). But when we speak about issues, can we say: ‘Allaah and His Messenger know best’? Or should we stick to simply, ‘Allaah knows best’?

The scholars have mentioned that during the lifetime of the Prophet (salallaahu ‘alayhe wasallam) you would say, ‘Allaah and His Messenger know best.’ But after the death of the Prophet (salallaahu ‘alayhe wasallam), we affirm knowledge for Allaah (subhaanahu wa ta’aala) Who is Alive and never dies.

The Messenger (salallaahu ‘alayhe wasallam) is not all aware of what is going on; he is not comprehensive in his knowledge of the situation you are facing. This is something specific to the Knowledge of Allaah. Allaah is Unique and Alone in the comprehensiveness of His Knowledge. He knows each and every affair. And this was something He conveyed through His Messenger (salallaahu ‘alayhe wasallam). So during the lifetime of the Messenger (salallaahu ‘alayhe wasallam), it would be befitting to acknowledge that by saying, ‘Allaah and His Messenger know best.’ But after his death (salallaahu ‘alayhe wasallam) the custom and tradition of the companions, the tabi’oon and the Imaams was to say, ‘Allaah knows best’ and not to say, ‘Allaah and His Messenger know best.’

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[1] Al-Bukhaaree (2856) and Muslim (30) Another narration of this hadeeth states: “…Then Mu’aadh narrated the above-mentioned hadeeth just before his death, being afraid of committing sin (by not telling the knowledge).” It is related by Al-Bukhaaree (128) and Muslim (32). It is stated in Fat-hul Majeed (Bestowal of the Glorious) (p28) that Al-Wazeer Abul Muzzaffar said: ‘Mu’aadh abstained from speaking out this hadeeth lest a benighted one would, out of his ignorance, abandon offering acts of disobedience.’

Source: Class 03: Explanation of Kitaab At-Tawheed by Ustaadh Moosaa Richardson based on the commentary of Shaykh Saalih Al-Fawzaan (hafidahullaahu ta'aala).