Hadith: He who has no integrity has no faith, and he who does not keep his covenant has no religion

عَنْ أَنَسِ بْنِ مَالِكٍ رَضِيَ اللَّهُ عَنْهُ قَالَ: مَا خَطَبَنَا نَبِيُّ اللهِ صَلَّى اللهُ عَلَيْهِ وَسَلَّمَ إِلَّا قَالَ:
«لَا إِيمَانَ لِمَنْ لَا أَمَانَةَ لَهُ، وَلَا دِينَ لِمَنْ لَا عَهْدَ لَهُ».
[حسن لغيره] - [رواه أحمد] - [مسند أحمد: 12383]

Anas ibn Mālik (may Allah be pleased with him) reported: The Prophet of Allah (may Allah's peace and blessings be upon him) never addressed us except that he said:
"He who has no integrity has no faith, and he who does not keep his covenant has no religion."
[Hasan/Sound by virtue of corroborating evidence] - [Narrated by Ahmad] - [Musnad Ahmad - 12383]

Explanation

Anas ibn Mālik (may Allah be pleased with him) informs that the Prophet (may Allah's peace and blessings be upon him) rarely delivered a sermon or gave advice without mentioning two things: First: There is no complete faith for he who harbors betrayal toward anyone regarding his wealth, person, or family. Second: There is no complete religion for he who betrays covenants and treaties and breaks them.

Benefits from the Hadith

1. Encouraging the fulfillment of trust and honoring covenants, as breaking them decreases faith.
2. Warning against betraying the trust and breaking covenants, and pointing out that this is one of the major sins.
3. The Hadīth includes the preservation of trust and covenant between Allah and His slave, as well as trust and covenant between individuals.