The Cheka and NKVD killed church faithful and priests all the time, especially early in the Soviet Union’s history. I remember reading one case where Cheka members poured molten metal into a priest’s mouth in a sacrilegious mockery of the eucharist.
You absolutely can be a Christian and support the working class, though I would argue you cannot be a Christian and a Marxist and absolutely not be someone who supports the Soviet Union, which oppressed the church and the faithful for years
