Narrated Abdullah:It is a sign of having knowledge that, when you do not know something, you say: 'Allah knows better.' Allah said to his Prophet:

'Say: No wage do I ask of you for this (Qur'an), nor am I one of the pretenders (a person who pretends things which do not exist)' (38.86) When the Quraish troubled and stood against the Prophet he said, "O Allah! Help me against them by afflicting them with seven years of famine like the seven years of Joseph." So they were stricken with a year of famine during which they ate bones and dead animals because of too much suffering, and one of them would see something like smoke between him and the sky because of hunger. Then they said: Our Lord! Remove the torment from us, really we are believers. (44.12) And then it was said to the Prophet (by Allah), "If we remove it from them. they will revert to their ways (of heathenism)." So the Prophet invoked his Lord, who removed the punishment from them, but later they reverted (to heathenism), whereupon Allah punished them on the day of the Battle of Badr, and that is what Allah's Statement indicates:

'Then watch for the day that the sky will bring forth a kind of smoke plainly visible...we will indeed (then) exact retribution.' (44.10). Bukhari Volume 6, Book 60, Number 347:

Narrated 'Abdullah: The best talk (speech) is Allah's Book 'Quran), and the best way is the way of Muhammad, and the worst matters are the heresies (those new things which are introduced into the religion); and whatever you have been promised will surely come to pass, and you cannot escape (it). Bukhari Volume 9, Book 92, Number 382

Guidance comes only from the two inspirations, the Quran and the Sunnah. The Quran is described as the best of all speech. If this is the case, then it must contain in it the best of all matters in all that is needed by mankind. The sunnah, the best guidance, is superior to all other philosophies and methodologies that mankind has invented, for the Sunah is the perfect example of the worship of Allah, manifested in the life and actions of the Prophet (saw). All that is opposed to the Quran and Sunnah – and is this opposition lies the source of all evil – are termed newly invented innovations, destined to the fire of Hell.

The Prophet (saw) said: "The intelligent one is the one who holds himself responsible and works for what is after death. And the incompetent one is the one who indulges himself in pursuit of personal desire and importunes God .

Narrated Abu Huraira: I heard Allah's Apostle saying, "I have been sent with Jawami al-Kalim (i.e., the shortest expression carrying the widest meanings), and I was made victorious with awe (caste into the hearts of the enemy), and while I was sleeping, the keys of the treasures of the earth were brought to me and were put in my hand." Muhammad said, Jawami'-al-Kalim means that Allah expresses in one or two statements or thereabouts the numerous matters that used to be written in the books revealed before (the coming of) the Prophet. Bukhari Volume 9, Book 87, Number 141.

Al-‘Aqeedah al-Tahhaawiyyah is a book dealing with ‘aqeedah (basic tenets of faith) which was written by Imam al-Tahhaawi and named after him.  The author is the imam, muhaddith and faqeeh Abu Ja’far Ahmad ibn Muhammad ibn Salaamah al-Tahhaawi – who is named after a village in Upper Egypt – he studied with many Shaykhs and learned from them and benefited from them, and he listed their number as three hundred Shaykhs. 

Al-‘Aqeedah al-Waasitiyyah which deals with Tawheed al-Asmaa’ wa’l-Sifaat (The Oneness of the Divine names and attributes). This is one of the best books written on this topic, and it is worth reading and studying.

Buloogh al-Maraam, by al-Haafiz Ibn Hajar al-‘Asqallaani. This is a very useful book, especially because it mentions the narrators, and quoted the opinions of others scholars, who said whose hadeeth is saheeh and whose is da’eef, and he comments on the hadeeth to say whether they are saheeh or da’eef.

A primary rule that creates an obligation or duty by declaring an act to be obligatory, prohibited, recommended, disapproved, or permissible.