2wd3dwh - with all the sincerity of heart
Narrated Abu Hurairah [radhi-yAll‚hu 'anhu]:
The Prophet [sal-All‚hu 'alayhi wa sallam] said,

He will be the most blessed by my intercession
on the Day of Resurrection who says
La ilaha illallah
with all the sincerity of his heart.

(Sahih al-Bukhari)