In a Hadith, it is mentioned that:
اَلدُّعَاءُ مُخُّ اَلْعِبَادَةِ
‘Dua is the essence of worship.’ (Musnad Ahmed & Tirmidhi)
In fact in another Hadith it is mentioned:
عَنِ النُّعْمَانِ بْنِ بَشِيرٍ عَنِ النَّبِيِّ ‏- صلى الله عليه وسلم ‏-قَالَ: { إِنَّ اَلدُّعَاءَ هُوَ اَلْعِبَادَةُ }
‘Dua is worship.’ (Sunan Abu Dawood) If one ponders and reflects on the above Hadith one will realize that they are very clear, definite and absolute statements. How is it that we give so little attention to that described as both the ‘essence’ of worship as well as worship itself?

The reason for this is because we tend to look at the outward form of dua which, when compared to other acts of Ibadah (worship) is ‘less strenuous’ and ‘exertive’ in terms of time, place, language and physical exertion. While there are conducive and opportune moments when duas are accepted in relation to the above there are no restrictions or specifications on the act of dua. Dua can be made at any time, in any place, in any language, when a woman is in her menses and also in a state of ceremonial impurity.

Dua is the ultimate form of Abdiya (Bondsman-ship) in that it is an expression of one’s total dependence on Allah knowing that every single condition — good or bad, happy or sad, benefit or loss, wealth or poverty — is exclusively in the hands of Allah and that He alone is the ultimate Causer of causes.

Dua is that act which ‘connects’ the slave to his Master. The slave lifts his hands as begging bowls in an expression of begging as a beggar does. “O mankind! It is you who stand as beggars in your relation to Allah, and it is Allah Who is Free of all wants, worthy of all praise. (Al Fatir 35:15)

In all humility, with an attentive heart, having full hope in his Creator, Maker, Sustainer and Cherisher, one attracts the gaze of mercy of the Master Who feels shy in turning His slave away empty handed. If it is not in the nature of a mother to turn her child away empty handed no matter how disobedient a child may be, how is it possible that the One who is the most merciful and who has placed mercy in the hearts of all mothers turns away His slave, empty handed? How is it possible for the One Who becomes angry when His slaves do not supplicate to Him not to be happy when they do?

Continuously turning to Allah Almighty in dua is a sign of one’s conviction in Him and the more one turns to Him, the more one’s faith increases. Dua is a condition of the heart and conversation with one’s Maker in the language of one’s choice.
In the vocabulary of Islam, there are no such words as impossible, unattainable or insurmountable. Dua in times of ease is gratifying and engenders humility while at the same time it serves as an assurance of our duas being accepted in times of difficulty.

Dua in times of difficulty, accompanied by the shedding of tears is uplifting, invigorating, assuring, cleanses, refreshes and provides solace and relief to a broken heart.