Aba Abdillah al-Sadiq (as) shows how this ayah works: “ ‘If you are grateful, I will surely increase you [in favor]; but if you deny, indeed, My punishment is severe.’ ” (14:7)

“Once we were in the presence of abu ‘Abd Allah, ‘Alayhi al-Salam, in Mina (a place in Makkah). We were eating grapes when a man came asking for help. Imam told someone to give him a bunch. The man said, ‘I do not need this. I need dirhams.’ The Imam said, ‘May Allah grant you a great deal.’ The man went away and then came back saying, ‘Give me that bunch of grapes.’ The Imam said, ‘May Allah give you a great deal and did not give him anything.’ Soon, another man came and asked for help. The Imam offered him just three pieces of grape that he accepted and said, ‘All praise belongs to Allah, the Lord of the worlds who has granted me sustenance.’ Abu ‘Abd Allah, ‘Alayhi al-Salam, said, ‘Wait,’ filled up both of his hands with grapes and gave it to him. The man took the grapes from the Imam and said, ‘All praise belongs to Allah, the Lord of the worlds.’ He (the Imam) then said, ‘Wait,’ and he (the Imam) asked his servant, saying, ‘How many dirhams do you have with you?’ We estimated there were about twenty dirhams with the servant. He gave them to the man, who took them and said, ‘All praise belongs to Allah. This is from You alone and You have no partners.’ Abu ‘Abd Allah, ‘Alayhi al-Salam, then said, ‘Wait,’ and he (the Imam) took off his shirt and said, ‘Wear this.’ The man took the shirt and said, ‘O abu ‘Abd Allah, all praise belongs to Allah who has granted me clothes and covering.’ Or he said, ‘O abu ‘Abd Allah, may Allah grant you good rewards. Nothing except this is left with abu ‘Abd Allah.’ He then left. We thought had he not prayed for ‘Abd Allah, he would keep giving him something as long as he kept praising Allah.’”

Sanad: Ahmad ibn Muhammad has narrated from ‘Uthman ibn ‘Isa from Misma’ ibn ‘Abd al-Malik who has said the above hadith

Source: al-Kafi, Volume 4, Chapter 37, Hadith #12 (See First Image below)

Grading: al-Majlisi said it is Reliable [Mir’at al-`Uqool, Volume 16, Page 179 (See Second Image below)]