Indeed deeds are based on intentions, and for each person is that what he intended.Deeds of speech or action, both outward and inner deeds – none are complete without intention (Niyyah), a fact that shows the great significance of intention in Islam. When one does a good deed without intention, he benefits nothing from that deed and Allah Almighty doesn't accept it from him.
And for each person is that which he intended.If by his deed, one sincerely worships Allah, seeking His pleasure alone, then from Allah he will have a reward; but if he intended some worldly benefit, making his worship a means of achieving that benefit, or if he had a wicked intention, then his is that which he intended, and his accountability is with Allah.
The Second Hadith:
The lawful is clear and the unlawful is clear…In the plain verses of His Book, Allah clarified this for, and the Messenger of Allah (SAW) explained it to us in his pure Shari'ah. The lawful is clear: it is that which souls find comfort in, matters in which there is no doubt whatsoever; and that the unlawful is clear for one who wishes to stay away from it. Between the lawful and unlawful are matters that are not so clear. If a Muslim stays away from those matters, he will have safeguarded his religion and honor. But whoever hovers around those matters will necessarily fall into what is prohibited. We must fear Allah in our sayings and deeds, taking the clear path that Allah and His Messenger (SAW) delineated for us. In a Hadith:
Leave that which causes you doubt to that which doesn't cause you doubt.Meaning, leave that which you are not sure about – is it lawful and harmless or not? And instead go to that which you have certain knowledge about – that it is indeed lawful and harmless.
The Third Hadith:
From the goodness of one's Islam is to leave that which does not concern him.Under Islam come faith and Ihsan. This Hadith is one of the foundations of the religion. The Muslim is described with one of two qualities: he is either one who is upright, obeying Allah and His Messenger's commandments, staying away from meaningless matters – then he is the true Muslim. Then there is one who follows up on meaningless speech and action, not deeming himself to be above rumors and false speech – he has deviated from the true and upright religion. Let us consider the Prophet's saying:
The Muslim is he from whom the Muslims are safe, safe from his tongue and his hand.The Fourth Hadith:
Whoever introduces into this matter of ours that which is not from it, then it is rejected.This proves that every innovation introduced in the religion – meaning that it doesn't have a basis in the Qur'an or Sunnah, ragardless of whether it is a saying or a deed, such as those deeds that Allah didn't legislate and the Prophet Muhammad (SAW) didn't command us with – then it is rejected for the one who introduced it. This is because his action is not founded on the Qur'an and Sunnah. Whoever's action is in agreement with Allah's Book and His Messenger's Sunnah, his action is accepted – by the Will of Allah.
[Credit goes to 'What Must Be Known About Islam', a comprehensive book, compiled by Muhammad bin 'Ali Al-Arfaj, translated by Darussalam, global leaders in Islamic books.]