Explanation

The meaning in a few plain lines

"A man from among those who were before you was called to account", i.e. a man from the previous nations was held accountable by Allah for the actions he had done. "No good deeds were found in his record", i.e. he had done no righteous deeds that bring one closer to Allah, the Almighty. "Except that he, being a rich man, used to enter into transactions with people", i.e. he used to conduct business transactions with them and give them loans. "And used to command his servants to show leniency towards those who were insolvent", i.e. he ordered his servants to be tolerant with those who cannot pay back their debts by giving them respite or by reducing their debt. "Allah, the Exalted, said: We are more entitled to this (leniency) than him. Pardon him", i.e. Allah forgave him as a reward for his kind treatment of people and his gentleness and leniency with them.