1) Knowledge - of its meaning, in what negates it and what affirms it.
“except for those who bear witness to the truth knowingly” – i.e., that there is no god except Allaah (laa ilaaha ill-Allaah) – “and they know” – in their hearts the meaning of the words that they utter with their lips. [al-Zukhruf 43:86]
2) Certainty - of the heart about it.
“Only those are the believers who have believed in Allaah and His Messenger, and afterward doubt not but strive with their wealth and their lives for the Cause of Allaah. Those! They are the truthful”[al-Hujuraat 49:15]
3) Submission - with it, outwardly and inwardly.
Truly, when it was said to them: Laa ilaaha ill-Allaah (none has the right “to be worshipped but Allaah),” they puffed themselves up with pride (i.e. denied it). And (they) said: ‘Are we going to abandon our aalihah (gods) for the sake of a mad poet?’”[al-Saffaat 37:22-36]
4) Acceptance - of it, with nothing of its requirements and necessities being rejected.
“And whoever disbelieves, let not his disbelief grieve you (O Muhammad). To Us is their return, and We shall inform them what they have done…”[Luqmaan 31:23]
5) Sincerity - with respect to it.
“Say (O Muhammad): ‘Allaah Alone I worship by doing religious deeds sincerely for His sake only’”[az-Zumar 39:14]
6) Truthfulness - (about it) from the bottom of the heart and not just with the tongue.
“Do people think that they will be left alone because they say: ‘We believe,’ and will not be tested. And We indeed tested those who were before them. And Allaah will certainly make (it) known (the truth of) those who are true, and will certainly make (it) known (the falsehood of) those who are liars, (although Allaah knows all that before putting them to test)”[al-‘Ankaboot 29:2-3]
7) Love - of it and its people and having allegiance and emnity because of it.
“And of mankind are some who take (for worship) others besides Allaah as rivals (to Allaah). They love them as they love Allaah”[al-Baqarah 2:165]