John calls the Cana miracle the “first of his signs” and says Jesus “manifested his glory” through it (John 2:11). The result was that “his disciples believed in him” (John 2:11).
Jesus tells the servants to draw from the filled jars and bring it to the banquet supervisor. When he tastes it, the liquid is now wine, though he does not know its source. The servants do know, since they drew the water. The supervisor compliments the bridegroom for saving the best wine for later, reversing normal hosting practice. This scene is the closing movement of the Cana wedding story in John 2:1–11. The narrative has already shown a shortage, Jesus’ instruction to fill jars with water, and the servants’ quiet obedience.
John presents a public moment where Jesus’ private instruction becomes publicly verifiable. The servants obey Jesus, the banquet supervisor tastes what had been water and finds it is now wine, and the supervisor praises the bridegroom for unusually good hosting (verses 8–10).
A careful answer keeps the immediate passage, the book's argument, and the whole-Bible storyline together, so the question is answered in context instead of as a detached idea.
Start with John 2:11, then read the surrounding section so the answer stays connected to the passage's flow.
11This beginning of his signs Jesus did in Cana of Galilee, and revealed his glory. His disciples believed in him.