{Imaam Ibn al-Qayyim (may Allaah have mercy on him) } said:
“Duas and Ta’awwudhaat
[prayers seeking refuge with Allah]
are like a weapon, and a weapon is only
as good as the person who is using it;
It is not merely the matter of how sharp it is.
If the weapon is perfect and free of faults,
and the arm of the person using it is strong,
and there is nothing stopping him,
then he can lay waste the enemy.
But---
if any of these (3) three features are lacking,
then the effect will be lacking accordingly.”
A Little Note :
Sincerity in Dua means having the firm belief that the One upon Whom
you are calling ALLAH{Azza Wa Jall} is alone Able to meet your need.
['In Shaa Allah'.]
'Invite all to the way of thy Lord with wisdom
and beautiful preaching;
And consult with them in ways that are best and most gracious'.
{ Source ~Al Qur'an~ Surat An-Naĥl (The Bee) 16: A#125 }