Importance of Tawheed

Allah said :

“And I did not create the jinn and men except that they should worship me (alone).” (51:56)

So the reason for our creation, our whole purpose on this earth is to worship Allah alone.

and he said:

“And verily we sent among every umrah (community, nation) a messenger (proclaiming): ‘worship Allah (alone) and avoid (or keep away from) taghut (all false deities etc. i.e. do not worship taghut besides Allah).’ ” (16:36)

After creating us, Allah didn’t leave us without guidance, rather he sent prophets and messengers to clarify our purpose, to teach the people the truth and warn them from falsehood. Every single messenger called the people to worship Allah alone, and stay away from committing shirk.

and Allah said:

“and your lord has decreed you worship not but him” (17:23)

and he said:

“worship Allah and join none with him in worship” (4:36)

Also the prophet (sallallahu alyhi wasallam) said:

“Indeed Allah has forbidden for hell the person who testifies: ‘there is nothing worthy of worship in truth but Allah’, for the sake of only Allah.” (Bukhari, Muslim).

and he (sallallahu alayhi wasallam) once asked one of his companions:

“O Muadh, do you know is the right of Allah upon his salves and what is the right of the slaves upon Allah? He responded: ” Allah and his messenger know best.” The prophet continued, “the right of Allah upon his slave, is to worship him alone and to never associate anything with him. The right of the slaves upon him is to not punish any person who does not associate anything with him.” (Bukhari, Muslim)

So the only way a person can be successful in this life and the hereafter, and be saved from the punishment of the hellfire, is to worship Allah alone upon Tawheed.

Ibn Abbas (May Allah be pleased with him) narrated:

“when the prophet (sallallahu alayhi wasallam) sent Muadh to Yemen, he said to him, ‘You will go to the people of the scripture. So when you reach there invite them to testify that there is nothing worthy of worship in truth except Allah'” (Bukhari and ‘Muslim)

The first thing the prophet advised his companions to teach when going out to spread the message of islam was the Tawheed of Allah.

From all of the above it becomes clear that the most important thing for every Muslim to have knowledge of and understand before anything else is the the Tawheed of Allah.

[Source: Kitab At-Tawhid, by Shaykhul-Islam Muhammad Ibn Abdul Wahab. Publisher: Darusallam]