Alif-Lâm-Mîm. [These letters are one of the miracles of the Qur'ân and none but Allâh (Alone) knows their meanings].

These are the letters of curiosity in order to test a person of his doubts about the commands of Allah.  No one knows the meaning of these letters, including the Prophet Muhammed, which also shows how true he was. This shows us how truly the Quran has been delivered to mankind, these letters are a seal for the the accuracy of the Quran. This also judges the writers of the Quran, every single thing has been noted precisely. 

These letters in the Holy Quran are guarded by Allah, no one can try and remove these letters, saying that they are just alphabets. These letters of curiosity convince us about the originality of the Quran, and how it has been preserved accurately without the change of a single letter.

The writers who use to note revelation never questioned or laughed on the Prophet, upon the revelation of these letters, even though they themselves were highly literate in Arabic. We can see the devotion of these noble individuals, and how precisely they wrote and collected every single precious letter in the Holy Quran.

Whatever Allah has revealed, the Noble Prophet has transferred it to us, the Prophet did not add a single word to try and explain these kind of letters in the Qur'an (such as, "alif lam meem", "nuun", "qaaf", etc.") 

In order for us to be deserving to call ourselves Muslims, we must adhere and implement the Quran and the Examples of our Noble Prophet.

Obey the laws of Allah and his Prophet,  what is learned from here is the way the Prophet Muhammed, and his companions, never said "but" or "why" when it came to the commands of Allah. They always followed and obeyed them, this is why those noble individuals were very succesful. Allah is our owner, master, creator, sustainer, and our eternal provider. Each and every soul and body belongs only to Allah, and the soul should never disobey the laws of Allah and add his own smartness and doubts to it. 

In this lifetime, there are only two ways. Either to follow the commands of Allah and the way of his Prophet, or to follow the way of Satan. The results of adhering to the way of Satan will be endless suffering in this life, the grave, and in the fire of hell. 

Whenever we leave the commands of Allah and the examples of the Prophet we automatically fall in the hands of Satan. It is the accursed Satan who fills us with doubts, and make our minds occupied in worldly matters. And gives us ideas in order to give our worldly matters a first priority making us leave the laws of Allah behind, and being disobedient to what has been ordained upon us. 

As we know, this world for us is a short time, regardless what we are earning and building in this world. Once we die, we will go empty handed and live a never ending life in the hereafter. So it really is not worth it to keep any doubts, or to leave the commands of Allah behind being obedient to Satan, keeping one's worldly affairs with a first priority.