Is he who does not wish well for his brother considered deficient in faith and sinful, despite his repeated attempts to rid himself of this habit?

Loving good for Muslims is a sign of complete faith, and its absence indicates a deficiency in faith. So, whoever does not love for his brother what he loves for himself in terms of good is deficient in his obligatory faith and has committed something forbidden. This matter is easy for a sound heart, but difficult for a heart afflicted with envy or deceit. This means that none of your faith is complete until he loves for his brother in Islam what he loves for himself. Fulfilling this is achieved by loving for him the attainment of such good from a source that does not cause him rivalry, so that the blessing upon his brother does not diminish anything from the blessing upon him. Just as the negation of faith from one who does not love for his brother what he loves for himself indicates that this is one of the qualities and obligations of faith.