"Living water" What did Jesus mean?

[dreadnought]

"He who believes in Me, as the Scripture said, ‘From his innermost being will flow rivers of living water.’” But this He spoke of the Spirit, whom those who believed in Him were to receive; for the Spirit was not yet given, because Jesus was not yet glorified." (John 7:38-39)

What do you think Jesus was talking about? Does it have to do with a baptism of Spirit within Chrisitians or something else?

Once a pastor prayed for me and it felt like water flowing inside of me, first upward, then downward, then up again ...

Maybe this sheds some light on the subject:

But he answered, "It is written, `Man shall not live by bread alone, but by every word that proceeds from the mouth of God.'" Matt 4:4 RSV