The heat of the moment and the heat of the issue: both cause believers to lose sight of the obvious - sin is a global issue, not a single issue, and it resides in the hearts of all mankind.
Christians forget their battle is not against flesh and blood (individuals) but against forces of darkness in heavenly places (Ephesians 6:12), not against single issues but against the lust of the eyes, the lust of the flesh, and the boastful pride of life (1 John 2:15-16).
Truth says, "No one can do everything!" ... besides, some hills are just not worth dying on, let alone climbing. In spite of secular hype for multitasking, working on everything at once is dissipating, wearying, and inefficient to the homo sapien. For example ...While there is a temptation for Christians to label whatever is not in keeping with [their view of] sound doctrine as heresy, the Bible seems to make the distinction that heresy is not merely the opposite of orthodoxy. Rather -Satan has done a frighteningly good job of distracting us from the real battle (he is not referred to by the Lord as "the father of lies" for no mean purpose (John 8:44). He is able to get well-intentioned but non-discerning Christians so wound up over single or peripheral issues they fail to discern reality.- heresy is a divisive teaching or practice which forces those who call themselves Christians to separate from it or face condemnation for it.John the Apostle gave a prime example of such a doctrine: denying the true nature of the person and work of Jesus Christ (1 John 4:1-3; 2 John 1:7-11). [Source; my emphases][This picture is from an 80s Moody Monthly issue;
if you know the artist let me know so I can give proper accreditation.]
They are then frustrated because no one else sees Christian mission as they see it ("why isn't she working as hard as I am," "why don't they do it my way," "why would they want to do it that way, any idiot can see my way is better," "that won't work, but I know a way that will"). Frustration then turns to fault-finding in order to assuage a very guilty conscience.
Some members of the Body of Christ are so busy pointing fingers at what is wrong with others, they fail to see the huge chinks in their own armor (if they wear any at all).
For instance, they may attend a bible study, where they hear, over several weeks, several hours of good teaching; suddenly their sensory neurons pick up one statement they don't agree with ... the next day they solemnly announce, "I can't go back there; not if he's going to continue to teach false doctrine."
This makes them a gossip, a backbiter, and apparently the sole arbiter of what is acceptable teaching in the church. For someone seeking an excuse to leave a bible study, any excuse is adequate. Sadly, they busy themselves trying to recruit others to join them, "If we don't stop her, she'll kill our church."
Thank God for the discerning amongst us, those who don't fall for Satan's deceptions.