حَدَّثَنَا عَلِيُّ بْنُ اَلْحُسَيْنِ بْنِ اَلصَّلْتِ رَضِيَ اَللَّهُ عَنْهُ قَالَ حَدَّثَنَا مُحَمَّدُ بْنُ أَحْمَدَ بْنِ عَلِيِّ بْنِ اَلصَّلْتِ عَنْ عَمِّهِ أَبِي طَالِبٍ عَبْدِ اَللَّهِ بْنِ اَلصَّلْتِ عَنْ يُونُسَ بْنِ عَبْدِ اَلرَّحْمَنِ قَالَ: قُلْتُ لِأَبِي اَلْحَسَنِ مُوسَی‌ بْنِ جَعْفَرٍ عَلَيْهِمَا السَّلاَمُ لِأَيِّ عِلَّةٍ عَرَجَ اَللَّهُ بِنَبِيِّهِ صَلَّی‌ اَللَّهُ عَلَيْهِ وَ آلِهِ إِلَی‌ اَلسَّمَاءِ وَ مِنْهَا إِلَی‌ سِدْرَةِ اَلْمُنْتَهَی‌ وَ مِنْهَا إِلَی‌ حُجُبِ اَلنُّورِ وَ خَاطَبَهُ وَ نَاجَاهُ هُنَاكَ وَ اَللَّهُ لاَ يُوصَفُ بِمَكَانٍ فَقَالَ عَلَيْهِ السَّلاَمُ إِنَّ اَللَّهَ تَبَارَكَ وَ تَعَالَی‌ لاَ يُوصَفُ بِمَكَانٍ وَ لاَ يَجْرِي عَلَيْهِ زَمَانٌ وَ لَكِنَّهُ عَزَّ وَ جَلَّ أَرَادَ أَنْ يُشَرِّفَ بِهِ مَلاَئِكَتَهُ وَ سُكَّانَ سَمَاوَاتِهِ وَ يُكْرِمَهُمْ بِمُشَاهَدَتِهِ وَ يُرِيَهُ مِنْ عَجَائِبِ عَظَمَتِهِ مَا يُخْبِرُ بِهِ بَعْدَ هُبُوطِهِ وَ لَيْسَ ذَلِكَ عَلَی‌ مَا يَقُولُ اَلْمُشَبِّهُونَ - سُبْحٰانَ اَللّٰهِ وَ تَعٰالی‌ٰ عَمّٰا يُشْرِكُونَ 

Narrated from Yunus ibn Abd al-Rahman, who said:

I said to Abu al-Hasan, Musa ibn Jafar (عليه السلام):

"For what reason did Allah take His Prophet (صلى الله عليه وآله) to ascend to the heavens, and from there to the Lote Tree of the Utmost Boundary (Sidrat al-Muntaha), and from there to the Veils of Light (Hijab al-Noor), and addressed him and whispered (entrusted a secret) to him there, when Allah cannot be described by a place?"

The Imam (عليه السلام) replied, "Indeed, Allah (تبارك وتعالى), is not described by place, nor does time apply to Him. But Allah (عز وجل) intended to exalt His angels and the inhabitants of His heavens through him (i.e the Prophet), and to grant honor to them through seeing the Prophet, and to show the Prophet from the wonders of His greatness that which he would inform (his followers) after his descent. And it is not as the anthropomorphists (al-mushabbihun - those who attribute human-like qualities and a physical form to God) say - Glorified and Exalted is Allah above what they associate with Him."

[Source: al-Tawhid, Shaikh Saduq, Ch. 28, Hadith. 5]