Answer: It is cooperation between people in truth and goodness.

Examples of cooperation include:

. Cooperation in restoring rights

. Cooperation in preventing oppression

. Cooperation in fulfilling the needs of the people and the needy

. Cooperation in all goodness

. Non-Cooperation in sin, harm, and transgression

Allah Almighty says: {Cooperate with one another in goodness and righteousness, and do not cooperate in sin and transgression. And fear Allah, for Allah is severe in punishment.} [Surat al-Mā’idah: 2] The Prophet (may Allah's peace and blessings be upon him) said: "The relationship of the believer with another believer is like (the bricks of) a building, each strengthens the other." [Agreed upon] The Prophet (may Allah's peace and blessings be upon him) also said: "A Muslim is the brother of a Muslim; he does not wrong him and he does not hand him over to an oppressor. Whoever fulfills the needs of his brother, Allah will fulfill his needs; and whoever relieves a Muslim of a burden, Allah will relieve him of a burden from the burdens of the Day of Judgment; and whoever covers (the faults of) a Muslim, Allah will cover (his faults) on the Day of Judgment." [Agreed upon]