This is Holy Week in the Orthodox Church.
"The Greek Orthodox tradition is for eggs to be dyed red
on Holy Thursday in commemoration of the Last Supper…."
See more at: http://usa.greekreporter.com/2015/04/07/
why-do-greeks-dye-easter-eggs-red-how-to-do-it/
The Borisov CV is from Math Humor for Holy Week.
See as well yesterday's posts Translation and Easter Translation.