At least twice in the gospel of Luke, Luke shows how the Word is to be preferred to a sign.
In the parable of the rich man and Lazarus, while the rich man suffers in hell, he begs Abraham to send a risen Lazarus to warns his brothers, arguing that “If someone goes to them from the dead, they will repent” (LUke 16:30).
Father Abraham says, “Nah, they have the Old Testament. That’s enough. Signs will do no better” (Luke 16:31; my paraphrase).
Later, when Jesus encounters the two men on the road to Emmaus who are mourning the death of the one they thought (based on the OT) was to be the redeemer, Jesus could have very easily opened their eyes immediately to see him, the resurrected Savior. Surely such a sign would have been the best and most direct route to faith for these two men.
Yet Jesus instead points them to the OT (Luke 24:27), to the words that they had believed only a part of (Luke 24:25). In fact, it is not until he leaves that they understand, “That was him.”
In this day when people are desperately seeking signs as reasons to believe, we should follow the example of Abraham and Jesus. Point people to the Word.
It’s not that signs don’t work. John reports that Jesus did many signs in order to bring belief.
It’s rather that the Word does work, and it needs nothing else. We need not live in an age of miracles in order to see the gospel spread. We need not be able to call down fire from heaven, or bread or healing or any other thing from heaven.
We need to take seriously the Word given to create life and bring belief in the lives of those who hear it.