Good Infection

Today's Reading

Read John 15:4-5: "Abide in me, and I in you. As the branch cannot bear fruit by itself, unless it abides in the vine, neither can you, unless you abide in me. I am the vine; you are the branches. Whoever abides in me and I in him, he it is that bears much fruit, for apart from me you can do nothing."

Then read Galatians 2:20: "I have been crucified with Christ. It is no longer I who live, but Christ who lives in me. And the life I now live in the flesh I live by faith in the Son of God, who loved me and gave himself for me."

Reflection

Lewis introduces one of his most vivid metaphors: the Christian life as a "good infection." Just as a disease spreads from person to person, so the life of Christ — the divine life of the Trinity — is meant to spread from Him to us.

This is not merely moral improvement. Lewis is careful to distinguish between what he calls "bios" (biological life, the natural life all creatures share) and "zoe" (the uncreated, eternal life of God). Christianity claims that human beings are meant to receive not just a better version of their natural life but an entirely different kind of life — the life that has always existed within the Trinity.

"He came to this world and became a man in order to spread to other men the kind of life He has — by what I call 'good infection.' Every Christian is to become a little Christ."

This is what it means to be "born again" — not just to turn over a new leaf but to receive a new nature. The branch does not produce its own fruit; it receives the life of the vine and fruit happens as a consequence.

"Every Christian is to become a little Christ. The whole purpose of becoming a Christian is simply nothing else."

Paul describes this experience with startling directness in Galatians: "It is no longer I who live, but Christ who lives in me." This is not a metaphor for Paul. It is a description of the most fundamental reality of his existence. His old self — the self-reliant, self-righteous Pharisee — has been crucified. What lives now is a new self, animated by the life of Christ.

Jesus's vine-and-branches image in John 15 captures the same truth from the other side. The Christian life is not fundamentally about trying harder but about staying connected to the source of life.

Going Deeper

Lewis's "good infection" metaphor challenges two common misunderstandings. First, Christianity is not primarily a moral code — it is a relationship that produces moral transformation as a byproduct. Second, the Christian life is not self-powered — it runs on a life that comes from outside ourselves.

The practical question is simple: are you trying to generate the Christian life from your own resources, or are you receiving it from Christ? The difference between those two approaches is the difference between exhaustion and abundance.