Regarding contemplation upon the Quran and the Sunnah, Allah Says what means: “And We sent not before you except men to whom We revealed [Our message]. So ask the people of the message [i.e., former scriptures] if you do not know. [We sent them] with clear proofs and written ordinances. And We revealed to you the message [i.e., the Quran] that you may make clear to the people what was sent down to them and that they might give thought.” [Quran 16: 43-44]
Another type of contemplation is over the evil end that others have come to, such as where Allah Says what means: “Do they not contemplate within themselves? Allah has not created the heavens and the earth and what is between them except in truth and for a specified term. And indeed, many of the people, in the meeting with their Lord, are disbelievers. Have they not travelled through the earth and observed how was the end of those before them? They were greater than them in power, and they plowed the earth and built it up more than they [i.e., the Makkans] have built it up, and their messengers came to them with clear evidences. And Allah would not ever have wronged them, but they were wronging themselves.” [Quran 30: 8-9]
Another type is to contemplate over the power of the Quran and its effect on other creations of Allah, and then think about how one should react. Allah Says what means: “Not equal are the companions of the Fire and the companions of Paradise. The companions of Paradise – they are the attainers [of success]. If We had sent down this Quran upon a mountain, you would have seen it humbled and breaking down from fear of Allah. And these examples We present to the people that perhaps they will give thought." [Quran 59: 20-21]
The Prophet taught us contemplation. When he awoke for the optional night-prayer, he would look to the skies and then recite the this following verse in which Allah Says what means: “[Those] 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…'” [Quran 3: 191]
Therefore, it is Sunnah to recite this verse before one begins his optional night-prayers. There is another opinion which states that he would recite it after praying his two Rak’ah Sunnah for the Fajr prayer.
Contemplation of scholars assists them to produce sound rulings, thereby causing them to reach sound opinions regarding particular matters…Contemplation increases one's faith.
The most important fruit that results from contemplation is knowledge, and once the heart increases in knowledge, its condition changes noticeably for the better, this directly reflects on the limbs and consequently improves the overall status of a person.
What does it mean to contemplate over oneself? It includes contemplating over how Allah has created his body and form, as well as to contemplate over one's shortcomings, which is vital because nobody can reform himself without contemplating over his shortcomings in order to correct them and rectify himself.
What did the famous Muslim reformers and rejuvenators do in order to change the condition of their people? There can be no doubt that the very first thing they did was to contemplate over the situation of their people in order to ascertain what they lacked and identify where the problems lied, and then, they began reformation by fighting ignorance, sinfulness and other such matters.
Contemplating over the creation of Allah makes one recognise wonders that are proof of the wisdom of Allah and His ability. Things that exist are either known or unknown to man, and there are new scientific discoveries daily of matters that have already existed but were unknown to man, but man will never be able to arrive at the essence of some of these matters, such as the human soul for example, which the west has endeavoured to discover, and this is the difference between us and them; therefore, Muslims do not waste any time trying to discover its reality because Allah Says what means: “…Say, 'the soul is of the affairs [i.e., concern] of my Lord…” [Quran 17: 85]
Likewise, trying to discover the essence of angels comes in the same category. Thus, contemplation over such matters should only be done in light of the texts from the Quran and the Sunnah.
Some scholars said a thousand years ago: “One of the signs of the greatness of Allah is His creation of man from a single drop of sperm.” There are wonders in the way man was created, yet he is heedless, whilst Allah Says what means: “And in yourselves [there are signs]. Then will you not see?” [Quran 51: 21] Allah mentions in many places of the Quran the creation of man from a drop of sperm, and this repetition is for reminding us to contemplate over our creation.
Just contemplate! If this drop of sperm were to be left in the air, it would smell horribly after a short time. Allah caused it be ejaculated from the male and created man from it. Note how Allah joins the husband and wife and establishes love between them, due to which they have sexual intercourse, from which this filthy drop emerges from the man and settles in the woman’s womb.
Note how He creates from this white drop a red blood clot, then forms it into an embryo and after this He divides the embryo into bones, nerves, veins and flesh; then He forms from these the head, hands, legs, fingers, toes and inner body parts, each having a distinct shape, a special location, a particular task and operation, and so on.
Also, note how the bones, which are the strong and solid part of the body, are also created from a drop of sperm, which yield these bones that form the structure over which man is built; note how each bone has a special form, some small and others large, some hollow and others solid; and since man needs to be mobile, Allah did not make these bones as one piece, rather, He created many bones with joints and ligaments connecting them in order to facilitate man’s movement. The bones in man's head number more than fifty and all have different shapes, yet Allah put them together in such a way as to make the shape of the head circular.
The mention of numbers and details is not meant simply for information, but rather, so that we can think of the greatness of the Creator. If any bone were missing, or there were more than the number required, then this would be considered as a defect, and this is what concerns doctors, while the people of vision contemplate over the greatness of Allah who created man in the best form and shape.
If all of this was created from a single drop of sperm, then what about the creation of the earth, the heavens, and the galaxies? Allah Says what means: “The creation of the heavens and earth is greater than the creation of mankind, but most of the people do not know." [Quran 40 :57]
After knowing these facts, go back to thinking about the drop of sperm; consider, if all of mankind and Jinn were to collectively endeavour to create anything from this drop, would they be able to? The fact is that they cannot even create a fly, let alone a human being.