Islam urges the Muslim to seek useful knowledge whether this useful knowledge is related to different Islamic sciences or not. Islam also considers seeking knowledge is a key to gaining Allah’s pleasure in the Hereafter. Mu`adh ibn Jabal (may Allah be pleased with him) said, “Seek knowledge, for seeking it for the sake of Allah is a sign of consciousness of Allah; acquiring it is an act of worship; studying it is a glorification (of Allah); and searching for it is (a kind of) jihad (striving in Allah’s cause)…”

With this in mind, we see that there is nothing wrong with inquiring about the reasons behind a given judgment or the wisdom behind a stated statement. Indeed, this is a good way of being certain regarding the knowledge one is seeking. However, too much argument is not at all recommended as it will end up putting one in a vicious circle. Thus, as seekers of knowledge, go and make arguments and raise question marks but be aware not to strip from the right path or allow the accursed Satan to overwhelm your thinking by dragging you to the realm of doubting everything you are taught or told.

The etiquette of the seeker of knowledge especially religious knowledge has been explained by Sheikh M. S. Al-Munajjid, a prominent Saudi Muslim lecturer and author, in which he states the following:

There is a certain amount of etiquette for seeking knowledge that the seeker of knowledge should follow. We will give every student of knowledge this advice and this etiquette for seeking knowledge; may Allah cause them to benefit thereby.
1. Be patient and persevering
Seeking knowledge is one of the highest of pursuits, and heights cannot be scaled except by working hard and patiently.
So be patient and persevere. If Jihad requires an hour of patience, then the seeker of knowledge must be patient until the end of his life. Almighty Allah says: (O you who believe! Endure and be more patient (than your enemy), and guard your territory by stationing army units permanently at the places from where the enemy can attack you, and fear Allah, so that you may be successful.) (Aal `Imran 3:3)
2. Have pure intention in what you do
Adhere to purity of intention in what you do. Let your aim be to seek the Face of Allah (i.e., the pleasure of Allah) and the abode of the Hereafter. Beware of showing off and loving to make yourself appear to be superior to your peers. The Messenger of Allah (peace and blessings be upon him) said: “Whoever seeks knowledge in order to compete with the scholars or to prove himself superior to the ignorant or to make the people look up to him, Allah will cause him to enter Hell.” (An-Nasa’i).
to sum up, you have to be pure both outwardly and inwardly from every major and minor sin.
3. Act upon what you know
Know that acting upon what you know is the fruit of knowledge. Whoever knows but does not act upon his knowledge is like the Jews whom Allah likened to the ugliest things in His Book, when He said: (The likeness of those who were entrusted with the (obligation of the) Tawrat (Torah) (i.e. to obey its commandments and to practise its laws), but who
subsequently failed in those (obligations), is as the likeness of a donkey which carries huge burdens of books (but understands nothing from them). How bad is the example of people who deny the Ayat (proofs, evidences, verses, signs, revelations, etc.) of Allah. And Allah guides not the people who are Zalimun (polytheists, wrongdoers, disbelievers).
) (Al-Jumu`ah 62:5)
and whoever acts without knowledge is like the Christians, who have gone astray as mentioned in Surat al-Fatihah.
4. Always be aware that Allah is watching
You must always be aware that Allah is watching you, in secret and in the open. Your attitude towards your Lord must always be balanced between fear and hope, which for the Muslims are like the two wings of a bird. Turn to Allah wholeheartedly and let your heart be filled with love for Him, your tongue with remembrance of Him (dhikr). Be happy and rejoice in His rulings and His wisdom.
always call upon Allah (du`aa’) in every sujud (prostration), asking Him to bless you and grant you beneficial knowledge, for if you are sincere towards Allah, He will support you and help you, and will cause you to attain the level of the righteous scholars.
5. Make the best use of time
Spend the most of your youth and your whole life in learning. Do not be deceived by procrastination and wishful thinking about the future. Every hour of your life that passes cannot be replaced. Do away with whatever you can of distractions and obstacles that prevent you from striving your utmost to attain knowledge. Hence the salaf (righteous predecessors) encouraged keeping away from one’s family and keeping a distance from one’s homeland, because when a person is distracted he will not be able to understand facts of knowledge and subtle issues. Allah has not given man two hearts in his chest, and similarly it is said that knowledge will not give you a part of it until you give it your all.
6. Be cautious
Beware of being preoccupied in the beginning with the disputes among the scholars, or among people in general, because this confuses the mind. Instead, give your all to the book that you are reading or the topic that you are studying until you become competent in it. Beware of moving from one book to another (before completing the former), for that is a sign of boredom and failure. You must pay attention to each branch of knowledge, in order of importance.
7. Be precise and focused
Strive to verify what you want to memorize so that you are certain of it, either from a sheikh or from someone else who can help you. Then memorize it properly and continually repeat it and review at specific times each day, lest you forget what you have memorized.
8. Study books
After you have memorized the summarized books properly, along with their commentaries, and you have understood any difficult passages in them and understood the important points, then move on to studying the detailed versions, always reviewing what you have learned and noting the valuable points, subtle issues, strange minor issues, solutions to problems, and differences between similar rulings, in all branches of knowledge. Do not think little of anything useful that you learn or any basic principle that you understand; instead, hasten to note and memorize it.
Let your concern to seek knowledge be uppermost; do not be content to learn only a little when you are able to do more. Do not be content with a little of the legacy of the Prophets (peace and blessings be upon them), and do not delay learning anything that you can or be distracted or put off by wishful thinking. Delay is a problem, and if you learn something now you can learn something else later.
Make the most of your time, when you are free and when you are busy. Make the most of your youth when your mind is fresh and you have fewer distractions, before you become distracted by false ambitions and the desire for worldly possessions.
You should try to obtain as many of the books you need as you can because they are the tools of learning. Do not make getting and keeping a lot of them (without benefiting from them) the only share of knowledge that you have, and collecting them the only share of understanding that you have. You also have to use and benefit from them as much as you can.
9. Choose good companions
Strive to choose righteous friends who are preoccupied with seeking knowledge and are of a good nature, who can help you in achieving your aim, add to the benefits you have already gained, encourage you to seek more knowledge, stop you from feeling bored and tired, who are religiously-committed, trustworthy and of good character, who are sincere towards Allah and who are not merely messing about.
Beware of the bad companion, for he may influence you. People are like birds, they will resemble one another (i.e., “Birds of a feather flock together”). So beware of mixing with bad people, for that is a sickness, and prevention is better than cure.
10. Have good manners towards the sheikh/teacher
Knowledge cannot be gained only from books; you must also have a sheikh whom you trust to open the door to knowledge and keep you from making mistakes. So you must have good manners towards him, for this is the way to success, learning and strength. So you must honor, respect and be polite to the sheikh. Observe the utmost standards of etiquette when you sit with your sheikh and speak with him. Ask questions in a proper manner and listen attentively. Be polite when studying the book with him and do not try to argue or compete with him. Do not initiate conversation with him, or walk ahead of him, or speak too much in his presence, or interrupt when he is teaching. Do not pressure him to give you an answer, and avoid asking too many questions, especially in front of other people, for this will make you appear to be showing off and make him bored with you. Do not call him directly by his name or nickname; rather say “O my sheikh” or “O our sheikh” (Ya shaykhi or Ya shaykhana).
If you think that the sheikh has made a mistake, do not let that make him lose respect in your eyes, because that will deprive you of his knowledge. Who is there who is entirely free from error?