Some of the Apocryphal texts of the New Testament report that Jesus worked miracles since His earliest childhood. However, for John, Jesus’ first miracle takes place in Cana of Galilee, at a wedding feast.
As the water in the jars, normally used for ritual cleansing, is transformed into wine we see that this sign shows forth Jesus as the Son of God and the One through whom the entirety of creation came into being (cf. John 1:3).
A new creation is heralded into the world by Jesus and a new religion is born out of Jewish practices: a religion that focused on cultic rules and ritual cleansing (symbolized in the water) is transformed in one which nourishes the faithful, offers the perfect cultic sacrifice, gives joy to the heart, and still has power to wash away all stains (symbolized by the wine in the cleansing jars). This later idea will be more and more important as we journey towards the celebration of Lent and Holy Week.