Just as when a child is taught the basics of writing and the basics of speaking and anunciating, s/he has to be taught this gradually, bit by bit, so if s/he continues to do this, s/he improves till s/he is eventually able to write and speak well. Knowledge, likewise has its young and its old, depending on the amount of understanding and their actions;
Isn't anything in this knowledge that is simple.

Malik, an Islamic scholar, when it was said to him that this is from the simple part of knowledge replied: There is nothing easy in the knowledge. Allaah has said: "Verily we shall send down to you a weighty word."
 So one who considers knowledge to be weighty and difficult will obtain it. But as for one who takes issues up saying: this is clear, and this is straightforward..., such a person will just pass over it rapidly and in doing so will lose out on a lot. Therefore, it is imperative to take things step by step in the acquisition of knowledge with the idea that nothing in it is simple - rather that all of it is weighty, with regards to its understanding, with regards to consolidating what is known, and with regards to persevering in acquiring knowledge; for it is weighty and it requires continuance and following up - for knowledge is forgotten if it is left, but if a knowledge seeker perseveres in it and continues, it will remain. ( Shaikh Saleh ibn Abdul-Azeez Aal-Sheikh, Seeking Knowledge and One's Intentions, http://salafipublications.com)

The beneficial knowledge has certain ways and means by which it is obtained and certain paths that are taken in its acquisition and memorisation. Allah says in Quraan: “And say: O Lord, increase me in knowledge [Taa Haa 21:114]

  And the Prophet Muhammad used to say: "O Allaah, benefit me with what you have taught me and teach me that which will benefit me and increase me in knowledge."

And for this reason one of the wise people, upon being questioned, "What is the way by which knowledge is obtained?", answered: "With eagerness is it followed, with love is it listened to, with sole concern is it gathered, [teach your knowledge to the one who is ignorant, and learn from the one who teaches, for if you do that, you will come to know what you were ignorant of and you will memorise that which you (yourself)  have learnt." And for this reason, Imaam ash-Shaafi'ee an Islamic scholar said: My brother! You will not acquire knowledge except by six matters: Intelligence, zeal, striving, competence/proficiency, the companionship of a teacher, and a long time! Acting upon the knowledge, the Prophet Muhammad said: "A servants two feet will not move on the Day of Judgement until he is questioned about four (things): His youth, how he spent it, his knowledge, how he acted upon it, his wealth, how he earned it and how he spent it and his body, how he used/wasted it." ( Saeed bin Wahf al-Qahtani, Guidelines For Acquiring Knowledge, http://salafipublications.com)

Islam is a religion based upon knowledge. The text of the Quran is replete with verses inviting man to use his intellect, to ponder, to think and to know, for the goal of human life is to discover the Truth which is none other than worshipping God in His Oneness. The Hadith literature is also full of references to the importance of knowledge. Such sayings of the Prophet as "Seek knowledge from the cradle to the grave", (Hadith) and "Verily the men of knowledge are the inheritors of the prophets", (Hadith) have echoed throughout the history of Islam and incited Muslims to seek knowledge wherever it might be found. During most of its history, Islamic civilization has been witness to a veritable celebration of knowledge. That is why every traditional Islamic city possessed public and private libraries and some cities like Cordoba and Baghdad boasted of libraries with over 400,000 books. Such cities also had bookstores, some of which sold a large number of titles. That is also why the scholar has always been held in the highest esteem in Islamic society. (Islam, Knowledge, and Science, http://www.usc.edu/dept/MSA)

The Prophet used to teach the Sunnah to his companions in word and deed, and urged them to follow it, as he said in his hadeeth: “Adhere to my Sunnah” and “Whoever neglects my Sunnah does not belong to me.” ‘Abd-Allaah ibn Mas’ood narrated that the Prophet Muhammad said: “There is no Prophet whom Allaah sent to any nation before me, but he had disciples from among his nation, and companions who followed his Sunnah and obeyed his commands.” (Narrated by Muslim, no. 71).( Adhering to the Sunnah of the Prophet, http://www.usc.edu/dept/MSA)

The  Prophet Muhammad lived according to the Qur'an, he was the true spirit of the Qur'an. This was so that others would follow his example and because it is the way Allah has commanded man to behave. The goal was to make the companions of the Prophet and Believers adopt a way of life that was of a True Muslim.

Jafar son of Abbu Talib acting as the Muslim spokesman to the king of neighbouring Abyssinia summarized the teachings of Muhammad to explain their situation thus:

“O King! We were living in ignorance, idolatory and immorality. We honoured no relative and assisted no neighbour. The strong among us exploited the weak. Then God sent us a prophet, one of our own people whose descent, conduct and good faith and morality we are all well acquainted. He called us to the unity of God, and taught us not to associate any other being with him. He forbade us the worship of idols which we and our fathers used to worship. He commanded us always to speak the truth, to remain true to our trust, to love the relatives and to be good neighbours. He forbade us to slander the virtuous women or consume the property of the orphans. He ordered us to fly from vices and to abstain from the evil, to offer prayers, to give alms and to keep the fast. We believed in him; we followed him. Our people, however, persecuted us and sought to bring us back to idolatory and their other abominations. As they made life intolerable for us in Mecca, we chose your country and came here to live under your protection in peace.”

The king refused to deliver up the refugees and the Quraish returned to Mecca discomforted. (Zahur-ul-Haque, Muhammad the Greatest Leader, pp. 51-53)