The scholar, Imam Muhammad Bin Abdul Wahhab (may Allah have mercy upon him said):
When it is said: “What is the comprehensive worship for Allah alone”?
I said: “Obeying Him by conforming to His commands and warding off things He has forbidden”. And when it is said: “What are the kinds of Ibaadah (worship) which are not allowed to any one besides Allah”?
I said: Among those kinds are:
1. Dua’a (Invocation)
2. Isti'anah (Asking for help)
3. Istigathah (Seeking help)
4. Zabh (Sacrifice)
5. Nazr (Vow)
6. Khauf (Fear)
7. Raja (Hope)
8. Tawakkul (Trust)
9. Inabah (Turning in repentance)
10. Mahabbah (Love)
11. Khash'ya (fear)
12. Rag bah (Wish)
13. Rahbah (Fear)
14. Ta'alluh (Exaltation)
15. Ruku' (Bowing down)
16. Sujud (Prostration)
17. Khushu' (Submissiveness)
18. Glorification (Directed to Allah alone)