A Christian and a non-Christian, standing side by side, won't look any different from each other. They might speak the same language and come from the same background. They might work at the same job and drive the same car. They might be, at first look, mostly indistinct.
But then there's what is unseen by the naked eye. Before Jesus Christ returned to the Father, he promised that he'd send the Holy Spirit of God to live in his disciples. The Spirit would be their special companion and leader for the rest of this life. This Spirit would dwell within them, God with his people.
Christ still sends his Spirit to his people. The Holy Spirit still today dwells within Christians. And by the power of the Spirit, Christians live truly new, different, and altogether changed lives.
This is Life in the Spirit.