The phrase "unhealthy preoccupation" means obsessively thinking about or focusing too much on something in a way that can be harmful or detrimental to one's physical or mental well-being. Full definition
«Ever since the Black Plague swept through Europe, Western Christianity has had an unhealthy preoccupation with what happens to people after they die» (redeeminggod.com)
Victorian anxiety about sexual desire, the lust of the «flesh» against the «spirit,» is an unhealthy preoccupation that betrays a fear of sin and death. (religion-online.org)
Ever since the Black Plague swept through Europe, Western Christianity has had an unhealthy preoccupation with what happens to people after they die, and as a result, has often read the Bible through life - after - death colored glasses so that everything seems to be teaching about what happens to people after they die. (redeeminggod.com)