As Muslims Islam should govern all our affairs.
فَلَا وَرَبِّكَ لَا يُؤْمِنُونَ حَتَّىٰ يُحَكِّمُوكَ فِيمَا شَجَرَ بَيْنَهُمْ ثُمَّ لَا يَجِدُوا فِي أَنفُسِهِمْ حَرَجًا مِّمَّا قَضَيْتَ وَيُسَلِّمُوا تَسْلِيمًا
But no, by your Lord, they will not [truly] believe until they make you, [O Muhammad], judge concerning that over which they dispute among themselves and then find within themselves no discomfort from what you have judged and submit in [full, willing] submission.(An-Nisa, 4:65)
As such the pure belief is of primary importance. It is the message of all the Prophets. From prophet to prophet their legislation differed, such as the Jews who were not allowed to work on the sabath, but the primary message was always the same. Worship Allah alone and do not associate any partners with him.
It is what will save us from eternity in hellfire. The simple pure belief that we all carry in our fitrah but has been corrupted by society. There is no Islam without this. A Muslim who prays, fasts, gives in charity but doesn’t do it to please his Creator, is wasting his time.
As such we could imagine a society with many of the rules of shariah, but lacking the aqeedah of Islam, failing despite having the rules. Because truly rules mean nothing unless they are enforced, free from corruption, and motivated by fear of punishment and hope for reward.
For those who are governing society, who can avoid the punishments of the system, what would motivate them to do right and avoid wrong? It is only the knowledge that Allah is watching him, that his deeds are being recorded, and that a time will come where he is questioned and judged for everything he did. The Prophet said,
“I have only been sent to perfect good characteristics.”Narrated by al-Bukhaari in al-Adab al-Mufrad (273).
This is the essence of a Muslim and the essence of Islam. Everything in Islam elevates a Muslim. Not only do you perfect your relationship between ourselves and Allah, but also between ourselves and the rest of society.
As aqeedah is the motivating factor behind having a good moral character, aqeedah thus is the most important aspect in the life of a Muslim.
Those with incorrect aqeedah ultimately deviate. As we say at least 17 times a day in our prayers,
اهْدِنَا الصِّرَاطَ الْمُسْتَقِيمَ صِرَاطَ الَّذِينَ أَنْعَمْتَ عَلَيْهِمْ غَيْرِ الْمَغْضُوبِ عَلَيْهِمْ وَلَا الضَّالِّينَ
The path of those upon whom You have bestowed favor, not of those who have evoked [Your] anger or of those who are astray.(Al-Fatiha, 1:6-7)
We must not forget the Jews were Muslim. The Christians were Muslim. The difference between them and us, is they deviated from the straight path of Allah. Having incorrect aqeedah leads to things like grave worship, saint worship, worship of the mind.
Correct aqeedah leads to deeper eemaan. The sort of eemaan that changes nations by motivating people to do their utmost.
Sacrificing their time, and their bodies to do what is most pleasing to Allah.
Speaking the truth, even when it leads to imprisonment.
Dedicating one’s life to dawah and teaching Islam despite being paid little or nothing for it.
These are things that we as Muslims are lacking in today. Look what a small population of Muslims 1400 years ago did to spread Islam, and look at what 2 billion Muslims are doing today. We are not struggling and striving to live Islam.
Internalizing our knowledge of Allah means fearing and seeking to please Allah over fearing and seeking to please the people.
الَّذِينَ قَالَ لَهُمُ النَّاسُ إِنَّ النَّاسَ قَدْ جَمَعُوا لَكُمْ فَاخْشَوْهُمْ فَزَادَهُمْ إِيمَانًا وَقَالُوا حَسْبُنَا اللَّهُ وَنِعْمَ الْوَكِيلُ
Those to whom hypocrites said, “Indeed, the people have gathered against you, so fear them.” But it [merely] increased them in faith, and they said, “Sufficient for us is Allah, and [He is] the best Disposer of affairs.”(Aal-i-Imran, 3:173)
The Prophet Salla Allahu Alayhi wa Sallam gave Ibn Abbas golden advice related to Allah’s Qadr:
“Know that if the nations gathered together to benefit you, they could not benefit you unless Allah has decreed it for you. And if the nations gathered together to harm you, they could not harm you unless Allah has decreed it for you. The pens have been lifted and the pages have dried.”(Jami’ at-tirmidhi page 509 hadith no. 2516)
This knowledge keeps a person grounded. When evil comes to him, he can be patient knowing that ultimately it is from Allah and Allah wants good for him. And when good comes to him, he knows it is ultimately from Allah, so he remains humble and thankful to Allah.
Correct aqeedah is the cure to the sickness in this world. In Suratul Asr Allah says:
وَالْعَصْرِ إِنَّ الْإِنسَانَ لَفِي خُسْرٍ إِلَّا الَّذِينَ آمَنُوا وَعَمِلُوا الصَّالِحَاتِ وَتَوَاصَوْا بِالْحَقِّ وَتَوَاصَوْا بِالصَّبْرِ
By time,(1) Indeed, mankind is in loss,(2) Except for those who have believed and done righteous deeds and advised each other to truth and advised each other to patience.(Al-Asr, 103:1-3)
It’s not enough for the Muslim that he believes, but his family also must believe. His friends also must believe. His neighbors and the whole society at large also must believe.
The Muslim knows the best way of life is the way of Islam taught by the Prophet Muhammad Sallal Allahu alayhi wa sallam. He wants this for the whole of society and is constantly thinking of the best way to do so.
He’s not satisfied having Islam for himself. He’s not pushing this responsibility on others, but rather is doing the best that he can. In the end he knows Allah will judge us individually and is thus worried about being judged for his own efforts.
In the end correct belief in Allah is the foundation of a Muslim, and a Muslim is the foundation of a just and moral society. What could be of more importance than that?