The basis of the happiness (success, wellbeing. etc) of a person are three…
Imaam Ibnul Qayyim said, “The most mindless amongst the people is the one who strays at the end of his journey (i.e. end of his life) even though the destination is close (i.e. departure from this world).
“The intellects that are aided with (the means to sound guidance) regard the revelation which the Messenger (peace be upon him) was sent with as the truth that is in harmony with (sound) intellect and wisdom.
“The intellects that are forsaken (i.e. in misguidance) see a contradiction between sound intellect and the (unadulterated) divine texts, and between sound wisdom and the (unadulterated) divine ordainments.
“The closest path to attaining the Pleasure of Allaah are: Adherence to the (authentic) Sunnah and to restrict oneself to it – internally [i.e. in one’s heart, mind etc] and externally [i.e. by way of deeds]; to be constantly in need of Allaah and desiring His Countenance alone through speech and deeds.
“No one has ever attained Allaah’s (Pleasure, Guidance etc) except through these three affairs, and no one has been prevented from (attainting Allaah’s Pleasure, Guidance etc), except due to being separated from these three affairs or one of them.
“The basis of the happiness (success, wellbeing. etc) of a person (in this worldly life and Afterlife) are three, but each of them has its opposite, therefore whoever is deprived of one of them will encounter its opposite: Tawheed and its opposite is Shirk, the (authentic) Sunnah and its opposite innovation in religious affairs, obedience (to Allaah and His Messenger) and its opposite is disobedience.
“These three affairs are opposed by one thing and that is: the heart being deprived of Ar-Raghbah Fillaah Wa Feemaa Indahu, Wa Minar Rahbah Minhu Wa Mimmaa Indahu [i.e. the heart deprived of the fervent desire to seek Allaah’s Pleasure through acts of obedience and hoping for Allaah’s reward, and deprived of fear of Allaah and the reward Allaah has kept for those who feared Him].”
Source: Al-Fawaaid Page 167