"The Duties of Brotherhood," book XV, part ii of al-Ghazali's Alchemy
of Happiness translated by Muhammad Nur Abdus Salas (2002) spells out
one of that sage's most straightforward and systematic prescriptions
for interfacing with the "other." At the outset, al-Ghazali
expansively wraps all of humankind in the tolerant embrace of Tawhīd,
the oneness of God and all creation:

Know that the world is one stage of the stages of the journey to God
Most High. All in this station are travelers. Since the destination of
journey of this caravan of travelers is the same, they are all as one.
There must be friendship and unity among them and mutual aid. (Al-
Ghazzali,17)

The "friendship and brotherhood" that occur "for the sake of God Most
High" al-Ghazali calls "among the most meritorious forms of worship".
We must go beyond tepid abidance-tolerance, Ghazali urges, to the
loving embrace of one another. Al-Ghazali gives instances of God's
revealing to the Prophets Muhammad, David, and Jesus that friendships
are great gifts from God bringing with them grand rewards: