The Holy Trinity is one of the fundamental concepts of the Christian faith. It distinguishes Christianity from other Abrahamic religions: faith in the One God is both in Islam and in Judaism, but the concept of the Trinity is inherent only to Christianity. It is not surprising that such an important concept was reflected in iconography.
The Trinity is not only one of the most important concepts in Christianity, but also one of the most mysterious. “One in three faces” - it is impossible to understand, comprehend to the end, comprehend with the mind, it can only be taken for granted, sincerely believing. It is even more difficult to imagine the Holy Trinity in the form of a concrete visible image, but the writing of the icon requires just this, and the icon painters found a way out of the situation, relying on Holy Scripture.
Old Testament Trinity
The Old Testament tells of how God appeared to Abraham and Sarah in the form of three wanderers. The couple welcomed them warmly, not immediately realizing that they were facing the Triune God. This episode is one of the foundations of the Christian doctrine of the Holy Trinity, and it is precisely it that is often used to depict the Trinity on icons.
The trinity is depicted in the form of three angels sitting under a tree or at a table with a treat, sometimes Abraham and Sarah are present next to them.
The most famous icon of this kind is the Trinity by Andrei Rublev. The icon is remarkable for its laconicism - there is not a single superfluous detail in it: neither Abraham and Sarah near the angels, nor a "still life" on the table - only a cup that echoes the "cup of suffering" that God the Son has to drink. The figures of angels are perceived as a vicious circle, correlated with the concept of eternity.
