The Du'aa of the Muslim is Answered
|AUTHOR:||Saleem bin 'Eid Al-Hilaalee|
|SOURCE:||An-Nubadh al-Mustataabah fee ad-Da'waat al-Mustajaabah (pg. 6)|
Abu Hurairah (radyAllaahu ‘anhu) reported that Allaah’s Messenger (sallAllaahu ‘alayhi wa sallam) said: “Whoever does not ask from Allaah, He become angry at him.” 
In the previously quoted saying of the Prophet (sallAllaahu ‘alayhi wa sallam), there is proof that the supplication means requesting something from Allaah, through which His Contentment is attained. This is since not asking from Allaah out of pride and self-dependence is not permissible with respect to the Self-sufficient, the Most Praiseworthy.
A poet took the meaning of this hadeeth and put it into poetic form saying:
“Allaah becomes angry when you abandon asking Him,
whereas the Son of Adam becomes angry, when you ask him for something.”
Therefore, Allaah loves from His Servants that they ask Him and that they turn towards Him and that they manifest their destitution and lowliness in front of Him. And He has made it a duty upon Himself to not send them back disappointed and empty-handed, as His Messenger (sallAllaahu ‘alayhi wa sallam) has informed us:
“There is not a Muslim upon the earth that calls to Allaah with a supplication except that Allaah gives it to him or He removes some evil of equal proportion from him, so long as he doesn’t supplicate for something sinful or to sever family ties.”
So a man amongst the people said: “What if we ask numerous requests?”
He (sallAllaahu ‘alayhi wa sallam) said: “Allaah is akthar (Able to respond to numerous requests).” 
In this is a sufficient clarification of the fact that Allaah guarantees the answering of the supplications. This is however, according to its conditions. Thus, we shall go into detail with the discussion concerning it, its description, its conditions, its proper time and place and its etiquettes, as well as what invalidates it.
 Translator's Note: An authentic hadeeth reported by Ibn Maajah, At-Tirmdhee, Al-Haakim and others
 Saheeh: I have checked it and provided its references in Saheeh Kitaab Al-Adhkaar wa Da’eefihi(1223/920 & 1224/961)