In the Quran, if God presents a word that people are not expected to know, it first asks, “do you know what said item is? Then it goes on to explain and define what the said item is. For example:
83:7 Indeed, the book of the wicked is in Sijjeen.
83:8 Do you know what Sijjeen is?
83:9 A numerically structured book.
101:1 The Shocker.
101:2 What a shocker!
101:3 Do you have any idea what the Shocker is?
101:4 That is the day when the people come out like swarms of butterflies.
104:4 Never; he will be thrown into the Devastator.
104:5 Do you know what the Devastator is?
104:6 GOD’s blazing Hellfire.
104:7 It burns them inside out.
This shows that God is aware of what terminology He needs to explain to his servants, as He has perfect knowledge of what we know and don’t know.
Interestingly, never in the Quran does it need to explain what are the rituals of our religion e.g. Contact Prayer (Salat), Obligatory Charity (Zakat), Fasting (Sayem), or Pilgrimmage (Hajj). This shows that God expets the readers of His book to already know these concepts and therefore do not need to be explained.
The knowledge of these rituals have been known among the Arabs since Abraham, who was formally instructed on how to perform these practices.
21:72 And we granted him Isaac and Jacob as a gift, and we made them both righteous. 21:73 We made them imams who guided in accordance with our commandments, and we instructed them how to work righteousness, and how to observe the Contact Prayers (Salat) and the obligatory charity (Zakat). To us, they were devoted worshipers.
Therefore, Muhammad and the followers of the Quran did not need to be told what these practices constitute, but were simply told to oberserve these practices by following the religion of Abraham (milat Ibrahim) – Monotheism (Hanif).
16:123 Then we instructed you (Muhammad) to follow the religion of Abraham, monotheism; he never was an idol worshiper.
Nowhere in the Quran did God need to explain what the religion of Abraham (milat Ibrahim), Monotheism (Hanif) was, or how to perform these rituals. Instead, we see that one of the first commandments in the Quran for the believers is to observe the Contact Prayers (Salat), and not the question, “Do you know what the Contact Prayer (Salat) is?”
2:2 This scripture is infallible; a beacon for the righteous; 2:3 who believe in the unseen, observe the Contact Prayers (Salat), and from our provisions to them, they give to charity.