But now thou wilt say: Who doth choose the love of his worship, credit or honour, instead of his God; I answer, that he that loveth his worship, as for to seem better and greater of estate than any other, and travaileth about it as much as he can; if he love it so much that for the getting, or keeping, or the saving of it, he breaketh the commandment of God, or breaketh love and charity to his neighbour, or is ready, or in full will to break it rather than he would forbear his worship, or lose anything of it, either in his name, or in his estate, or of fulfilling his will; soothly he sinneth deadly, for he loveth his worship, and chooseth it more than the love of God and of his neighbour. And nevertheless, the man that sinneth thus deadly will say with his mouth that he will not choose pride for his god, but he beguileth himself, for he chooseth it for his god in his deeds. (John Climacus)

I'm not entirely sure what Climacus is saying.

But my best guess is that anything we allow to complicate our relationship with God or neighbor is prideful idoltry.

Even if the complication might be celebration of the eucharist, but we so value a particular celebration that we alienate ourself from neighbors who celebrate otherwise. This is pride.

Even if we might be committed to serving the hungry, and are so engaged in this service that we will steal from the rich to give to the poor. This is pride.

We serve God and neighbor. All else is complement or distraction.

The image is of Madonna on a Cross.