We have been commanded to recite this Dua regularly.
Shayikh Sadooq narrates from Abdullah bin Sinan who says
that Imam Sadiq (a.s.) said,
"After this a time of such doubt will befall you that
you will be without the visible signs and a guiding Imam.
And no one shall be able to achieve salvation from this
except those who recite "Dua-e-Ghareeq."
(Supplication of the drowning man).
"YA ALLAHO YA REHMAN YA RAHEEM
YA MUQALLEBAL QULOOB SABBIT QALBI ALA DEENAIK"
O Allah! O Beneficent! O Merciful.O One who changes the hearts (of people)Give me steadfastness upon Your religion
iltemas e dua
-Sipah e Mahdi(a.t.f.s.)