The ʿaqīdah must come first because the only real cause for the differing and destruction that has come upon our Islamic world is the loss of purified ʿaqīdah.
The ʿaqīdah (creed) must come first because it is the foundation of the daʿwah (call) of the Prophets as Allāh the Exalted said upon the tongue of every Prophet He sent to his people:
يَا قَوْمِ اعْبُدُوا اللَّهَ مَا لَكُم مِّنْ إِلَٰهٍ غَيْرُهُ ۖ ﴿٨٤﴾
“O people! Worship Allāh, you do not have a deity other than Him.”
[Sūrah Hūd, 11:84]
The ʿaqīdah (creed) must come first because it is the decisive partition between abiding in the Fire (forever) and being saved from it. Have you not heard the statement of Allāh – Sublime is His Affair – :
إِنَّ اللَّهَ لَا يَغْفِرُ أَن يُشْرَكَ بِهِ وَيَغْفِرُ مَا دُونَ ذَٰلِكَ لِمَن يَشَاءُ ۚ وَمَن يُشْرِكْ بِاللَّهِ فَقَدِ افْتَرَىٰ إِثْمًا عَظِيمًا ﴿٤٨﴾
“Verily Allāh does not forgive that shirk (association) be made with Him, and He forgives whatever is less than that for whoever He wishes. And whoever commits shirk with Allāh, then he has indeed perpetrated a great sin.”
[Sūrah al-Nisāʾ, 4:48]
Shirk is the greatest of those things which negate Tawḥīd, which is the basis for the correctness of the correct ʿaqīdah.
The ʿaqīdah must come first because shirk with Allāh is the greatest form of oppression as Allāh the Exalted says:
إِنَّ الشِّرْكَ لَظُلْمٌ عَظِيمٌ ﴿١٣﴾
“Verily Shirk is indeed a great transgression.”
The ʿaqīdah must come first because the only real cause for the differing and destruction that has come upon our Islamic world is the loss of purified ʿaqīdah. So indeed the creed of many of the Muslims today has become corrupted by matters of greater shirk from making ṭawāf (encircling) the graves, and seeking help from the dead people inside of them, and trying to fulfill ones needs and affairs from them. So they return to the first jāhilīyyah (pre-Islamic times of ignorance), and it is as if they have not heard the statement of Allāh the Exalted:
إِن تَدْعُوهُمْ لَا يَسْمَعُوا دُعَاءَكُمْ وَلَوْ سَمِعُوا مَا اسْتَجَابُوا لَكُمْ ۖ وَيَوْمَ الْقِيَامَةِ يَكْفُرُونَ بِشِرْكِكُمْ ۚ وَلَا يُنَبِّئُكَ مِثْلُ خَبِيرٍ ﴿١٤﴾
“Verily those whom you call upon besides Allāh do not hear your calls. And if they were able to hear you, then they would not be able to answer you. And upon the Day of Judgement, they will disown your worship of them, and there is none like He who is the All-Knower.”
And we prohibit you from the innovations of the Ṣūfīyyah which many of the common folk of the Muslims have erected to (such) an educational level that whole countries have institutionalized these innovations, such as the celebration of the Birthday of the Prophet. And (innovations such as) accompanying the Christians in their festivals, not to mention the deviations in dealings and manners and other than that from that which separates their countries from the Book and the authenticated Sunnah, with the permission of Allāh, the Mighty and Majestic.
And after this beloved brother of mine, we have shown the truth of our statement that the ʿaqīdah must come first.1