The acknowledgement of Allaah is four things:
First– to acknowledge that Allaah exists and this is found in the fitrah of the creation, no one denies this except for the one who denies his own intellect and these people are a minority. And from them are those who said “I am your lord” externally like Firawn, though internally he still acknowledged Allaah as his Lord. However the majority of people are upon the fitrah and they acknowledge Allaah internally and externally.
Secondly, is to acknowledge the Rububiyyah, which is to acknowledge that Allaah alone is the One who creates, who sustains and maintains the affairs of His creation.
Thirdly, is to acknowledge the Tawheed of al-Asma was-Sifaat. We must know that the Creator is unique in His names and attributes and that there is nothing like Him, so we should confirm these names and attributes without denying them or altering their meanings.
Fourthly, is to acknowledge that He is One in Uloohiyyah; the purpose of life is to worship Allaah, as Allaah says:
“And I did not create jinn and mankind, except to worship Me” [Surah adh-dhariyaat:56]
So this is Uloohiyyah; and it means that He alone is the only One worthy of worship, anything else that is worshiped beside Allah is worshiped in falsehood.