In the name of Allah, Most Gracious, Most Merciful.
Here is a saying of Tsavri Sofian, a native of Kufa. He died in Basra in the year 161 (777-778).
“In four cases one acts under the influence of ignorance:
When one censors others; this relates to not recognizing the supreme decisions of the Lord Most High and whoever does not recognize these decisions falls into infidelity.
When one lets envy take hold inside our hearts; this relates to not accepting the apportionment determined by the Lord, for he who does not accept his share falls into infidelity.
When one earns wealth from sources that are forbidden or of questionable legitimacy; this relates to not worrying about the Account that will be taken on the Day of Judgment, and to not worry about that Account is the characteristic of the unfaithful.
When one no longer expects anything from the Lord; this comes from disregarding Allah’s Mercy, and whoever despairs of Allah’s Mercy is an infidel.”
“…and never give up hope of Allah’s Mercy. Certainly no one despairs of Allah’s Mercy, except the people who disbelieve.” (Koran 12.87)