Trinity

 The Trinity (Russian: Троица, tr. Troitsa, also called The Hospitality of Abraham) is an icon created by Russian painter Andrei Rublev in the 15th century. It is his most famous work and the most famous of all Russian icons, and it is regarded as one of the highest achievements of Russian art. Scholars believe that is it one of only two works of art (the other being the Dormition Cathedral frescoes in Vladimir) that can be attributed to Rublev with any sort of certainty.

(from Wikipedia)