Why did Asionov began to weep with Makar?

Aksionov has been imprisoned for years in a harsh Siberian labor camp since being wrongly convicted for the murder of a merchant. The real murderer, Makar, is imprisoned in the labor camp alongside Aksionov, but for a different offense. One day, Makar tries to escape from the camp by digging a tunnel. Aksionov knows about this, yet doesn't rat out Makar to the authorities after the tunnel is discovered, even though he rightly suspects that Makar's guilty of the murder for which he was unjustly convicted.
Makar is grateful for Aksionov's silence, and in a fit of remorse, confesses to him that he was indeed the man who killed the merchant all those years ago. Both men weep profusely, and for the same reason: the revelation of the truth, at long last, has lifted a huge weight from their shoulders. Makar had had to live with his guilt for so long, but now that the truth's out in the open, he no longer has to suffer. For his part, Aksionov has been unburdened of any bitterness he may have felt at his wrongful imprisonment. Though he still remains a prisoner in the labor camp, he has been freed from the past by Makar's emotional confession.