Jesus transforms everything

This is a very familiar story and so it can be easy to miss the point. Jesus changes water into wine: That is total transformation, changing one thing into another. He's not just adding something to the water but transforming the very nature of it, altering its molecular structure.  He's also changing shame into celebration: The fact that they had run out of wine was a massive failure in their task of hospitality to their guests, bringing shame onto their family. Jesus turns what would have been a shameful situation into a celebration. He totally turns the situation around.

The water and wine is symbolic of our state with and without Jesus. Throughout the Bible, wine symbolised joy and God's blessing. At this wedding they have run out, which symbolises that, at that time, there was a lot of religious behaviour but it was lacking joy and blessing from God. In that sense we have all run out of wine, we have turned our back on God and are looking elsewhere for joy and blessing, while ignoring the only person who can truly bring it.

Jesus has come to bring total conversion, not just a bit of modification to our behaviour or improvement in our attitude. He has come to transform us from sinners to saints, from His enemies to His friends, to move us from guilt to humble confidence before Him, and from shame to joy

How does He bring it? He brings it by his death. Jesus says to Mary "my hour has not yet come". The hour He is referring to is the cross. That is how this conversion, this transformation occurs. That is where "God made Him who knew no sin to become sin for us so that we could become the righteousness of God" (2 Cor 5:21).