In spite of the wide implications of the first two categories of Tawhid, firm belief in them alone is not sufficient to fulfill the Islamic requirements of Tawhid. Tawhid ar Rububiyyah and Tawhid al-Asma’ was-Sifat must be accompanied by their complement, Tawhid al-'Ibadah, in order for Tawhid to be considered complete according to Islam. This point is substantiated by the fact that Allah Himself has related in clear terms that the Mushrikun (idolators) of the Prophet's time confirmed many aspects of the first two forms of Tawhid. In the Qur'an Allah tells the Prophet (saws) to say to the pagans:

           "Say: 'Who is it that gives you all sustenance from the sky and earth, governs sight and hearing, brings forth life from dead (matter) and death from the living, and plans the affairs of man?' They will all say 'Allah'."( Q 10:31)

           The pagan Makkans all knew that Allah was their creator, sustainer, their Lord and Master yet that knowledge did not make them Muslims according to God. In fact, Allah said:   

             "Most of them do not believe in Allah except while joining partners to Him." (Q 12:106)       

          Consequently, the most important aspect of Tawhid is that of Tawhid al-Ibadah, maintaining the unity of Allah’s worship. All forms of worship must be directed only to Allah because He alone deserves worship, and it is He alone who can grant benefit to man as a result of His worship.

          Furthermore, there is no need for any form of intercessor or intermediary between man and God. Allah emphasized the importance of directing worship to Him alone by pointing out that this was the main purpose of man’s creation and the essence of the message brought by all the prophets. Allah says: 

           "And I did not create the Jinn and Mankind except they should worship Me (alone).” (Q 51:56).

           "Verily, We have sent to every nation a messenger (saying). “ Worship Allah and avoid false gods” (Q 16:36).

          Hence, God made Tawhid a part of man’s nature to worship Him, and He sent Prophets and books of Divine revelation to clarify the aspect of the purpose of creation which was with man’s mental ability to grasp. That purpose is, as previously mentioned: the worship of God (‘ibadah) and the main message of the Prophets were to worship God alone, Tawhid al-Ibadah. Consequently, the gravest sin is shirk, the worship of others instead of Allah or along with Allah.

         In Surah al-Fatihah, which every Muslim is required to recite in his or her prayers at least seventeen times daily, verse four reads,

           "You alone do we worship and from You alone do we seek help".

         A clear statement that all forms of worship should only be directed to the One who can respond, Allah. The Prophet Muhammad (saws) confirmed the concept of unity of worship saying,

            "If you ask in prayer ask only Allah, and if you seek help, seek it only from Allah"

          The absence of any need for intercession is further emphasized by the many verses indicating His closeness to man. For example:    

         "When My servants ask you (O Muhammad) about Me (tell them), 'Verily I am close (to them), I listen to the prayer of every one who calls on Me. So let them respond to Me and believe In Me in order that they may he guided aright."(Q2:186)

          The confirmation of Tawhid al-'Ibadah conversely necessitates the denial of all forms of intercession or association of partners with Allah. If someone prays to the dead seeking their influence on the lives of the living or the souls of those who have passed away, they have associated a partner with Allah, because worship is being shared between Allah and His creation. The Prophet Muhammad (saws) said, in no uncertain terms, "Prayer (du'a) is worship." And, Allah, Most Great and Glorious, said:           

            "Do you then worship besides Allah, things that can neither help nor harm you." (Q21:66). 

          Worship ('Ibadah) in the Islamic view, includes more than just fasting, paying Zakah, Hajj and animal sacrifices. It includes emotions like love, trust, and fear, all of which have degrees which should only be directed to God. Allah has addressed these emotions and warned against excesses in them as follows:

            "There are among men those who take (for worship) others besides Allah as equals to Him. They love them as they should only love Allah. But those who believe have a much greater love of Allah..." (Q 2:165).

             "Put your trust in Allah if you are truly believers."(Q 5:23)

           Since the term 'Ibadah means total obedience and Allah is considered the ultimate Lawgiver, the implementation of secular legal systems not based on divine law (Shari'ah) is an act of disbelief in the divine law and belief in the correctness of such systems, such a belief constitutes a form of worshipping other than Allah (Shirk). Allah said in the Qur'an: 

            "Those who do not rule by what Allah has revealed are disbelievers (Kafirun).” (Q 5:44).

         Hence, a significant part of Tawhid al-'Ibadah involves the implementation of Shari'ah, especially in lands where Muslims form the majority of the population. Divine law has to be re-introduced in the many so-called Muslim countries where governments now rule according to imported capitalist or communist constitutions, and Islamic law is either totally extinct or relegated to a few areas of minor importance. Likewise, Muslim countries, where Islamic law is on the books but secular laws are in force, have also to be brought in line with the Shari'ah as it pertains to all aspects of life. The acceptance of non-Islamic rule in place of Shari’ah in Muslim lands is Shirk and an act of Kufr. Those in a position to change it must do so, while those unable to do so must speak out against the rule of Kufr and call for the implementation of Shari'ah. If even this becomes impossible, un-Islamic government must be sincerely hated and despised for the pleasure of God and the upholding of Tawhid.