Contemplate on how Allah created the universe is a way to attain the knowledge

Allah the almighty said ( interpretation of the meaning ) : { Who remember Allah while standing or sitting or [lying] on their sides and give thought to the creation of the heavens and the earth, [saying], "Our Lord, You did not create this aimlessly; exalted are You [above such a thing]; then protect us from the punishment of the Fire.} 
Quran ( 3 : 191 )
That is, they deduce what they meant from creating the heavens and the earth. This means that thinking is an act of worship performed by the devoted slaves of Allah. Once they reflect upon it, they know that Allah did not create it in vain, so they learn and know that Allah is the true Creator.