What is your evangelistic R0?
There is a concept in infectious disease study called R0, (pronounced “R naught,”). You may have heard it mentioned on the news in reference to the coronavirus, but it long predates that disease. It is a mathematical term that indicates how contagious an infectious disease is. R0 tells you the average number of people who will contract a contagious disease from one person who has that disease. For example, if a disease has an R0 of 3, a person who has the disease will transmit it to an average of 3 other people, which means the disease is expanding rather rapidly. On the other hand, an R0 of .9 means the population with the disease is slowly shrinking and will hopefully eventually die out. In order to drive the R0 down, typically actions must be taken, like social distancing or a vaccine.
While there is not a lot of similarity between infectious disease and religion (though I have heard some atheists claim such a similarity), there is much to be learned from R0 in relation to the church. When Jesus gave the Great Commission[1], he was instructing his disciples to increase the R0 of the church. After all, if none of the followers ever told anyone else the good news (an R0 of zero), the church would have promptly disappeared. Rather, each of us is charged to spread the gospel widely so that the church can grow and thrive not only geographically, but through time as well.
Note that the R0 result is the average. This makes us ask the question, “What is my personal R0” or, asked another way, “Are my actions increasing the R0 of the church?”
[1] “Therefore go and make disciples of all nations, baptizing them in the name of the Father and of the Son and of the Holy Spirit,” Matthew 28:19, NIV.