I want to make a promise to you. After reading this, you’ll be prepared to show Mormon missionaries that the Bible disagrees with Joseph Smith and the Church of Jesus Christ of Latter-day Saints (also known as the LDS Church or Mormonism).

Before we get to this simple witnessing technique, there are two things you need to understand about Mormonism.

First, Mormons have four books they consider scripture: the Book of Mormon, Doctrine and Covenants, Pearl of Great Price, and the King James Bible. These books aren’t equally authoritative to Mormons, though. The Bible is considered the least important of the four. Here’s why.

In Pearl of Great Price, Joseph Smith lists thirteen articles of faith. The eighth article says, “We believe the Bible to be the word of God as far as it is translated correctly.” In Joseph Smith’s opinion, though, much of the Bible was lost or corrupted in translation after the death of the apostles.

Because of this alleged corruption, Mormons give priority to reading the “more important” Mormon holy books, which means they often aren’t familiar with what the Bible says. Despite their belief that the Bible has the least authority, Mormons still respect the Bible and will take seriously the verses you show them.

Second, Mormons mean two different things when they use the word “salvation.” In Doctrines of Salvation, Joseph Fielding Smith, the tenth LDS president, said, “Salvation is twofold: General—that which comes to all men irrespective of a belief (in this life) in Christ—and, Individual—that which man merits through his own acts through life and by obedience to the laws and ordinances of the gospel” (emphasis added).

Notice, general salvation isn’t based on any particular belief. The LDS Church teaches that all human beings are saved and will enter one of the three levels of Heaven. This benefit was secured for all mankind by Jesus’ death on the cross. Belief or faith in Jesus is not needed for general salvation.

Individual salvation, by contrast, is earned—merited through good works and obedience to the Mormon gospel. This type of salvation is often called “exaltation” by Mormons.

With these two things in mind, here’s the simple witnessing technique that will help you show that the Bible conflicts with the teaching of Joseph Smith.

After greeting the Mormon missionaries at your door, have them turn in their Bibles (or their app) to Ephesians 2:8–9. Here’s what their KJV says:

For by grace are ye saved through faith; and that not of yourselves: it is the gift of God: Not of works, lest any man should boast.

Have your Mormon friends read the verse out loud, then ask them to define general salvation and individual salvation according to their theology. Once they define these terms, ask them which type of salvation they think Paul is talking about in Ephesians 2:8–9.

If they say Paul is talking about general salvation, point out that verse 8 says salvation comes through faith. Faith isn’t necessary in the Mormon doctrine of general salvation, so Paul can’t be referring to that type of salvation.

If they say Paul is referring to individual salvation, point out that verse 9 says individual salvation isn’t attained through works. Works of obedience are necessary in the Mormon doctrine of individual salvation/exaltation, so Paul can’t be referring to that type of salvation either.

After pointing out Ephesians 2:8–9 isn’t referring to either doctrine of Mormon salvation, let your Mormon visitors wrestle with what Paul is saying. Then have them turn to Galatians 1:8–9 in their KJV and ask them to read it.

But though we, or an angel from heaven, preach any other gospel unto you than that which we have preached unto you, let him be accursed. As we said before, so say I now again, if any man preach any other gospel unto you than that ye have received, let him be accursed.

Even if an angel from Heaven brought the Mormon gospel, Paul warns us not to believe it. At this point, gently ask them if they know the gospel Paul preached. If they don’t, share the true gospel of salvation—Ephesians 2:8–9—with your Mormon visitors. Be sure to define your terms and explain it in a clear way.

Wrap everything up with this question: “If neither type of Mormon salvation is in view in Ephesians 2:8–9, and Paul says in Galatians 1:8–9 not to believe any other gospel than that which he preached, where does that leave the Mormon gospel?”

By using this simple method, you will help Mormon missionaries see that the Bible is at odds with the teachings of Joseph Smith and the LDS Church.