The Marks of a Christian

How do we know if someone is truly saved? Can we make this judgment? Yes we can, but not by looking at a persons heart (nobody can do that), but by observing the external marks of a true work of grace. Don’t go by a story of conversion either. But here are the marks: Do they believe in the essential truths of the Bible? Are they into their Bibles? Do they fellowship with other believers? Do they tell unbelievers how to be saved? Do they show a changed life?