What did C.S. Lewis mean when he wrote “Be ye perfect” is not idealistic gas?

In his chapter 9 of “Beyond Personality: Or First Steps in the Doctrine of the Trinity,” which can be found in his masterpiece Mere Christianity, Christian author C.S. Lewis wrote,

The command Be ye perfect is not idealistic gas. Nor is it a command to do the impossible. He is going to make us into creatures that can obey that command. He said (in the Bible) that we were “gods” and He is going to make good His words. If we let Him–for we can prevent Him, if we choose–He will make the feeblest and filthiest of us into a god or goddess, dazzling, radiant, immortal creature, pulsating all through with such energy and joy and wisdom and love as we cannot now imagine, a bright stainless mirror which reflect back to God perfectly (though, of course, on a smaller scale) His own boundless power and delight and goodness. The process will be long and in parts very painful; but that is what we are in for. Nothing less. He meant what He said.

Many Latter-day Saints have often cited this and other passages written by C.S. Lewis to make it appear that this philosopher’s beliefs were similar to Mormonism. First of all, we need to clarify. Lewis was not teaching that Matthew 5:48 (“Be ye therefore perfect, even as your Father which is in heaven is perfect”) had to be accomplished in this lifetime, whether the word “telios” really means “perfect” or, as many LDS leaders have explained, “complete.” In chapter 10 (“Nice People or New Men”), Lewis wrote,

Those who put themselves in His hands will become perfect, as He is perfect–perfect in love, wisdom, joy, beauty, and immortality. The change will not be completed in this life, for death is an important part of the treatment. How far the change will have gone before death in any particular Christian is uncertain.

For Lewis, perfection is something that is accomplished by God, if we let Him. Of course, the believer can prevent this process through disobedience. However, perfection is not something a person conjures up through good works. Depending on which LDS leader is talking, perfection may or may not be available in this lifetime. See here for more information.

Second, C.S. Lewis was not insinuating that the Christian believer can become a god or goddess in his or her own right. Rather, the believer will only mirror the glory that is possessed by God. As Lewis said, the glorified believer will be “a bright stainless mirror which reflect back to God perfectly (though, of course, on a smaller scale). When a person becomes a believer, he or she is a “new creature: old things are passed away; behold, all things are become new” (2 Cor. 5:17). Something incredible happens when a person invites the Holy Spirit to take over. She is human in the physical realm but, spiritually, becomes transformed and renewed. This doesn’t mean that a person becomes perfect on the spot, nor does it mean that the job will be accomplished this side of death. But incredible things will happen for a person accompanied by Jesus to heaven.

Meanwhile, all believers who have received the Holy Spirit are children of God and His heirs in this road to glorification. Romans 8:14-17 says,

For as many as are led by the Spirit of God, they are the sons of God. For ye have not received the spirit of bondage again to fear; but ye have received the Spirit of adoption, whereby we cry, Abba, Father. The Spirit itself beareth witness with our spirit, that we are the children of God: And if children, then heirs; heirs of God, and joint-heirs with Christ; if so be that we suffer with him, that we may be also glorified together.

Romans 8:30 adds,

Moreover whom he did predestinate, them he also called: and whom he called, them he also justified: and whom he justified, them he also glorified.

Glorification is the final destiny for those who are predestined, called, and justified. As Christian pastor John MacArthur writes, “Glorification is also the fulfillment of Jesus’s desire to see his church purified from all spot, wrinkle, or any such thing (cf. Eph. 5:27), dwelling with him for all eternity” (Biblical Doctrine, p. 654).

Third, C.S. Lewis is not suggesting that Christians will become gods– with the ability to have their own worlds–as Mormonism teaches. The Bible instructs that, as glorified beings, we can reflect the glory of God and Jesus. This is different from what Mormonism’s “eternal life” or “exaltation” teaches. Here are just a few quotes showing how these leaders teach this as truth:

10th President Joseph Fielding Smith: Joseph Smith taught a plurality of gods, and that man by obeying the commandments of God and keeping the whole law will eventually reach the power and exaltation by which he also will become a god” (Doctrines of Salvation 1:98).

12th President Spencer W. Kimball: Brethren, 225,000 of you are here tonight. I suppose 225,000 of you may become gods. There seems to be plenty of space out there in the universe. And the Lord has proved that he knows how to do it. I think he could make, or probably have us help make, worlds for all of us, for every one of us 225,000” (“The Privilege of Holding the Priesthood,” Ensign (Conference Edition), November 1975, p. 80).

Can you see the reasonable basis for belief that you can become a God like he is by progressing here and hereafter? (Book of Mormon Student Manual Religion 121 and 122, 1989, p. 58).

We can become Gods like our Heavenly Father. This is exaltation (Gospel Principles, 1985, p. 290).

By definition exaltation includes the ability to procreate the family unit throughout eternity. This our Father in heaven has power
to do. His marriage partner is our mother in heaven. We are their spirit children, born to them in the bonds of celestial marriage
(Achieving a Celestial Marriage, 1976, p. 129).

The Continuation of the Seeds Is Dependent on Celestial Marriage and a Celestial Resurrection (Achieving a Celestial Marriage,
1976, p. 135).

Fourth, I find it interesting that some Latter-day Saints often like to cite Lewis and dote on his ideas, especially those that seem to conform with their theology, but he never did get baptized by this church and he never joined it, despite the fact that he had to have known about this religion.

In conclusion, Lewis taught that “be ye perfect” was a process, with God working His majesty on the believer who does not fight the process. The believer must be willing to hand the keys to the car, so to speak, and allow Him to make him/her more like Him every day. It really is not idealistic gas!

For another look at Matthew 5:48, click here.