The church is vague about what types of ‘sins’ will keep you out of heaven. They utilize this ambiguity in a way to keep your mind thinking constantly about ALL your actions.
“…I cannot tell you all the things whereby ye may commit sin for there are divers ways & means even so many that I cannot number them but this much I can tell you that if ye do not watch yourselves & your thoughts & your words & your deeds & observe to keep the commandments of God & continue in the faith of what ye have heard concerning the coming of our Lord even unto the end of your lives ye must perish & now re O man remember & perish not—”
Mosiah 4:29-30 – The Handwritten Book of Mormon (West Valley City, UT: Dan Wees, August 2017), 207.
This type of instruction is so unclear that even the most devout members can never be certain if they’re doing good enough at any given time.