3 - Achieving authority and succession of rule (khilaafah) upon the earth, and [maintaining] purity of the Religion and firmness against the various destructive thoughts and ideologies; just as Allaah, the Exalted, said:
“Allaah has promised those amongst you who truly believe and act in obedience to Allaah and His Messenger, that He will grant them rulership upon the earth, just as He granted it to those before them, and that He will establish their Religion for them and grant them the authority to practice the Religion which He chose and ordered for them. And He will certainly change their situation to one of security, after their fear, providing they worship Me, obey Me, and do not associate anything else in worship with Me.” [Soorah an-Noor 24:55].
So Allaah has firmly tied the achievement of these lofty goals and objectives with worshipping Him alone and not worshipping others along with Him. And this is the meaning and requirement of laa illaaha illallaah.
4 - Achieving peace and tranquility of the soul, as well as mental and psychological relief for whoever says laa ilaaha illallaah and acts by its requirements. This is because such a person is a slave and worshipper of only one Lord. He knows what his Lord wants and what pleases Him, so he does it.
Likewise, he knows what angers Him, so he abstains from it. This is contrary to one who worships and is enslaved by many deities, each one desiring from him what the other does not desire, and each one planning and arranging for him something different to what the others plan and arrange. Allaah, the Most High, said:
“Are many different lords and deities better or Allaah, the One, the Irresistible?” [Soorah Yoosuf 12:39].
And Allaah the Most High said: “Allaah puts forth a similitude: a slave belonging to many partners who dispute and argue with one another and a slave who belongs entirely to one master. Are the two equal in comparison?” [Soorah az-Zumar 39:29].
Imaam Ibnul-Qayyim remarked: “This similitude that Allaah the Most Perfect strikes is like that of one who worships others besides Allaah (mushrik) and one who worships only Allaah (muwahhid). So the example of a mushrik is like a slave who is owned by a group [of masters] who constantly dispute, argue and show enmity towards each other; so the person becomes ill-natured. Thus, since the mushrik is one who worships different deities, he is likened to a slave who is owned by a group of masters who compete with one another to employ his service and obedience. It is therefore not possible for him to appease all of them!
On the other hand, the example of a muwahhid who worships Allaah alone is like a slave who has just one master to whom he submits. The slave knows the master’s intent and knows also the ways to please him. Thus he is relieved of all the feuds and confusion [that are bound to arise if he has more than one master]. Rather, he is safe from his master, with no dispute over who he should serve and obey, with the fact that the master shows clemency, mercy and kindness to him, does good to him, and looks after his best interests. So are the two slaves
(1) I’laamul-Muwaqqi’een (1/187).