source : Al Fawaid (taken from the English translation of the book) p. 134
The ignorant people complain to people about Allaah, and this is the highest degree of ignorance, for if he had known his Lord, he would not have complained about Him, and if he had known the people he would not have complained to them.
One of the predecessors saw a man complaining to another man about his poverty and dire necessity. He said to him, ‘O you! By Allaah, you have done nothing but complain about He who has mercy for you, to the one who has no mercy for you’.
The following verses have been mentioned about the meaning of the previous statement of the predecessor.
When you complain to a son of Adam
verily you complain about the Most Merciful
to the one who does not pity.
On the contrary, the person who is profoundly knowledgeable about Allaah complains to Allaah alone. And the most knowledgeable person about Allaah is the one who complains about himself to Allaah, and never to people. He complains about the causes that make people do wrong to him, for he knows about the following Qur’anic verses,
‘And whatever of misfortune befalls you it is because of what your hands have earned. And He pardons much’
(Ash-Shura, 42: 30)
‘Whatever of good reaches you, is from Allaah but whatever of evil befalls you, is from yourself.’
(An-Nisa, 4: 79)
‘(What is the matter with you?). When a single disaster smites you, although you smote (your enemies) with one twice as great, you say: ‘From where does this come to us?’ Say (to them), ‘It is from yourselves (because of your evil deeds). ‘And Allaah has power over all things.
(Al-Imran, 3: 165)
Therefore, there are three levels: the lowest one is to complain about Allaah to his creatures, the highest one is to complain about yourself to Him and the middle one is to complain about His creatures to Him. May Allaah make us from those who complain to Him alone about ourselves, He the Majestic and Most High, Ameen.