Du’ā is a form of worship
In Sūrah al Ghāfir V. 60, Allāh commands us to make du’ā to him and that those who dont do so due to their arrogance, Allāh threatens them with the Fire of Hell. Also the Prophet () in a hadīth narrated by Nu’mān ibn Basheer explicitly mentions, “Du’ā is worship” [Ahmad, the Four Sunans, Sahīh Al Jāmi’ #3407] and then the Prophet () recited the above verse form Sūrah al Ghāfir. Thus we see that du’ā is definitely a form of worship.
In another verse of Sūrah al Ghāfir V. 65, Allāh mentions that we must make du’ā to Him and making du’ā to Him is the dīn. No other act of worship has been paralleled with the entire dīn. Or connected to the entire concept of worship (ibādah).
Thus since we have established that du’ā is a form of worship just like any other act of worship like salāh (prayer) and siyām (fasting). And since its an established and agreed upon rule that the manner and ettiquette of performing any act of worship like salāh and siyām must be taken from the Qur’ān and the authentic Sunnah of the Prophet (), the same is the case with du’ā because it too is an act of worship like the others. Thus we restrain ourselves to the Qur’ān and Sunnah when it comes to the manner and ettiquette of du’ā.
May the Peace and Blessings of Allāh be upon the Prophet, his family and companions.