Allah the Exalted said,

﴿أَمْ لِلإِنسَـنِ مَا تَمَنَّى ﴾

(Or shall man have what he wishes), asserting that not everyone gets the goodness that he wishes,

﴿لَّيْسَ بِأَمَـنِيِّكُمْ وَلا أَمَانِىِّ أَهْلِ الْكِتَـبِ﴾

(It will not be in accordance with desires (of Muslims), nor those of the People of Scripture.)(4:123) Allah says, not everyone who claims to be guided is truly guided, and not everyone gets what he wishes for himself. Imam Ahmad recorded that Abu Hurayrah said that the Messenger of Allah said,

«إِذَا تَمَنَّى أَحَدُكُمْ فَلْيَنْظُرْ مَا يَتَمَنَّى، فَإِنَّهُ لَا يَدْرِي مَا يُكْتَبُ لَهُ مِنْ أُمْنِيَّتِه»

(When one of you wishes for something, let him be careful with what he wishes for, because he does not know what part of his wish will be written for him.)Only Ahmad collected this Hadith. Allah's statement,

﴿فَلِلَّهِ الاٌّخِرَةُ والاٍّولَى ﴾

(But to Allah belongs the last and the first.) meaning, all matters belong to Allah and He is the King and Owner of this world and the Hereafter, Who does what He will in both lives. Whatever He wills, occurs and whatever He does not will, never occurs.