I looked up the passage, 1 John 5:7-8, in my bible and the footnotes reference the later addition to some of the manuscripts. Looks like reading footnotes is valuable. ;)
Next to justification by Christ's sacrifice alone, I don't think there's any doctrine in Scripture as important and necessary to understand than the Trinity. Without it we are not Christians. So if someone chose to stress that point, I don't think it's so egregious. Nothing in the rest of 1 John 5 contradicts the verses. In fact, it supports them.
Let's ask forthedeclaration. What do you think about 1 John 5:7-8, ftd?
The footnotes don't tell you the whole story. The truth is those verses were added, thereby corrupting the scripture.
Try John 7:53-8:11 or Mark 16:9-20. Same story.