"O My servants who have believed, indeed My earth is spacious," in this verse He commanded them to emigrate to Medina. "So worship Me," meaning: in that land to which He commanded you to emigrate, namely, Medina.
Muhammad said: "So Me (fa-iyyaya)" is in the accusative case governed by an implied verb whose explanation is manifest; the meaning is: worship Me: so worship Me.
﴿يَا عِبَادِيَ الَّذِينَ آمَنُوا إِنَّ أرضي وَاسِعَة﴾ أَمَرَهُمُ فِي هَذِهِ الْآيَةِ بِالْهِجْرَةِ إِلَى الْمَدِينَة ﴿فأياي فاعبدون﴾ أَيْ: فِي تِلْكَ الْأَرْضِ الَّتِي أَمَرَكُمْ أَنْ تُهَاجِرُوا إِلَيْهَا، يَعْنِي: الْمَدِينَة.
قَالَ مُحَمَّد: (فإياي) مَنْصُوبٌ بِفِعْلٍ مُضْمَرٍ الَّذِي ظَهَرَ تَفْسِيرُهُ؛ الْمَعْنَى فَاعْبُدُوا إِيَّايَ: فَاعْبُدُونِ.
