A religious man, the one who used to say night prayers and cried in his vigil came to Imam Jawad (A.S) and politely sat down before Imam Jawad (A.S)and said: O son of the Messenger of Allah bless him and his family, I have come to see goodbye, I am going to go to Hajj pilgrimage. Imam Jawad (A.S) said to him: Are you not in debt to any one? He said, yes, I am O son of the Messenger of Allah, I just owe an atheist who you know him some money,
Imam (as) said:if you pay back his money, do have any money for your trip to Mecca?
The man said: no, then Imam Said: paying back his debt is Obligatory for you and going to Mecca is unlawful and forbidden.
Then Imam said the following sentence: فانّ المؤمن لايخون our Shias never betray. Imam said: pay back his money before evening, you need not go to Mecca, This is the sign of our religion.
source : erfan.ir