TAWHEED OF WORSHIP
Nothing Deserves Worship Except Allaah
If someone truly believes that Allaah is the only creator, owner, and controller of everything and that Allaah alone deserves the highest names and descriptions, yet he worships along with Allaah something else, then his acceptance of the other two types of Tawheed would never benefit him. For example, if a person completely believes in Tawheed of Lordship and Tawheed of Names and Descriptions, but he goes to the grave of some dead person, praying to him, making vows to him, and trying to get close to him, such a person is then a disbeliever in Allaah destined for the fire if he dies doing those things. This is because Allaah says in Qur'aan Surah Al-Maa'idah (5:72):
إِنَّهُ مَن يُشْرِكْ بِاللَّهِ فَقَدْ حَرَّمَ اللَّهُ عَلَيْهِ الْجَنَّةَ وَمَأْوَاهُ النَّارُ ۖ وَمَا لِلظَّالِمِينَ مِنْ أَنصَارٍ
"Surely whosoever worships others with Allaah, then Allaah has forbidden Paradise for him, his final place is the fire, and there will never be any helper for the transgressors."
Think about this: if someone believes Allaah is the only Lord and that He is the Most Merciful but that person worships other people by praying to someone other than Allaah, then how could his belief that Allaah is Lord and the Most Merciful help him? If he believes Allaah is the only Lord then why would he worship others? The Prophet (صلى الله عليه وسلم) said about the importance of Tawheed of Worship:
من مات لا يشرك بالله شيءا دَخَلَ الجنة، ومن مات يشرك به شيءا دَخَلَ النار
"Whoever dies without associating anything in worship with Allaah will enter Paradise, and whoever dies associating anything in worship with Him will enter the fire." Recorded by Imaam Muslim