Icon of Rakh in the Cathedral of Saint Basil in Moscow
In Russian iconography Rakh is the Repentant Thief, the fellow crucified next to Jesus, as the tale is told in the 23rd chapter of the Gospel called “of Luke” (no one really knows who wrote it; the earliest manuscripts are anonymous). And of course Luke just calls him a “malefactor,” κακούργος — kakourgos, meaning one who does bad, a criminal — not specifically a thief, which notion arises elsewhere.
And he said unto Jesus, Lord, remember me when thou comest into thy kingdom.
And Jesus said unto him, Verily I say unto thee, Today shalt thou be with me in paradise.
Now interestingly, this account disagrees with that of Matthew. In Matthew 27 we are told that two thieves (λησταί) were crucified with Jesus, but neither is repentant:
He trusted in God; let him deliver him now, if he will have him: for he said, I am the Son of God.
The thieves also, which were crucified with him, cast the same in his teeth.
The earliest gospel — that called “of Mark” — also has thieves, but in Mark (chapter 15) they are simply there to fulfil supposed prophecy. They neither scorn Jesus nor does either “repent”. The gospel called “of John” (chapter 19) merely mentions two other people being crucified with Jesus. It tells us nothing whatsoever about them.
So we see that only “Luke” tells us that one of the two crucified with Jesus was repentant, though he does not specify that the penitent was a thief. And that, combined with calling the two crucified with Jesus “thieves” in Matthew and Mark, along with the following from the apocryphal Gospel of Nicodemus, are the sources for icons of the Repentant Thief ... [see source]
It does not take much thought to realize that we are not dealing with history, but rather with hagiography — pious writings written for a purpose other than literal history. People often just “made things up.” But what we should note in these excerpts for our purposes here is that first, only one biblical gospel, that of Luke, tells us that one of the malefactors crucified with Jesus was “repentant” and was promised paradise. Second, we should note that this “repentant thief” is not named ... Russian icons call him Rakh. What makes this name even more puzzling is that the Greeks, from whom the Russians inherited a great many iconographic types, do not call the thief Rakh or even anything remotely similar. How did this name arise? ... [see source]
In Russian iconography, Rakh may be found in his own icons, carrying a cross ...
[excerpts from The Repentant Thief Who?]