By Shaykh ul-islam Muhammad bin Abdul wahhab ibn Sulaymaan at-tameemi. (رحمه الله تعالى)
Trans in English. Abu Naasir Abid ibn Basheer.
In the name of Allaah, the most Beneficent, The Most Merciful.
I ask Allaah, the Most Generous, The lord of the Throne, to protect you in this world and the Hereafter, and to bless you wherever you are and to make you from thos who are grateful when they are given, patient when they are tested and those who seek forgiveness when they sin. For verily, those are the three signs of happiness.
Know, may Allaah guide you to obeying Him, that Haneefiyyah is the religion of Ibraaheem (حنیفیّة مِلة ابراہیم): It is that you worship Allaah making the religion purely for Him, as He said:
وَمَا خَلَقْتُ الْجِنَّ وَالْإِنسَ إِلَّا لِيَعْبُدُونِ
And i have not created the Jinn and Mankind except to worship Me (Alone).
(Surah adh-Dhariyaat 51, ayah: 56)
When you acknowledge that Allaah has created you for His worship, then know that worship is not regarded as such unless it is accompanied by tawheed, just as prayer is not regarded as such unless it is accompanied by purification (taharah). So when shirk enters into worship it corrupts it just like an impurity invalidates Purification.
So when you recognize that if shirk enters into worship, it corrupts it, negates all the actions and the one who does it is eternally in the Hell-Fire, then you will realize the most important matter obligatory upon you: recognition of this fact, in order that Allaah may save you from the abyss of committing shirk with Him, about which He, the Most High said:
إِنَّ اللَّـهَ لَا يَغْفِرُ أَن يُشْرَكَ بِهِ وَيَغْفِرُ مَا دُونَ ذَٰلِكَ لِمَن يَشَاءُ ۚ
Verily, Allaah forgives not that partners should be set up with him in worship, but He forgives except that (anything else) to whom He pleases.
(Surah an-Nisah 4 ayah: 116)
And this knowledge comprises of four principles which Allaah, the Most High, has mentioned in His Book.
The first principle is that you know that Kuffaar, whom the Messenger (صلى الله عليه وسلم ) fought, used to affirm that Allaah, The Most High, was the Creator And the Disposer of all the affairs but that did not enter them into Islaam and the proof of His, The Most High's saying:
قُلْ مَن يَرْزُقُكُم مِّنَ السَّمَاءِ وَالْأَرْضِ أَمَّن يَمْلِكُ السَّمْعَ وَالْأَبْصَارَ وَمَن يُخْرِجُ الْحَيَّ مِنَ الْمَيِّتِ وَيُخْرِجُ الْمَيِّتَ مِنَ الْحَيِّ وَمَن يُدَبِّرُ الْأَمْرَ ۚ فَسَيَقُولُونَ اللَّـهُ ۚ فَقُلْ أَفَلَا تَتَّقُونَ
"Say: Who provides for you from the sky and from the earth? Or whom owns hearing and sight? And who brings out the living from the dead and brings out the dead from the living? And who disposes the affairs? They will say: Allaah. Say: Will you not be afraid of Allaah's Punishment (for setting up rivals in worship with Allaah)?
(Surah Younus 10, ayah: 31)
Explanation further Continue, In sha Allaah.