Fountain of living water is one of the names for God that later found fulfillment in Jesus (Yeshua‘). The NIV uses a slightly different name for God in the two verses in which the name occurs: Spring of living water. We can better understand its meaning by looking at the Hebrew words.
The Hebrew word for fountain (maqor) is related to the word for digging. Jeremiah chose maqor instead of the near cognate word mayan, which comes from ‘ayin, meaning a natural spring. Perhaps Jeremiah wanted to emphasize that having a relationship with God is like maintaining some springs; a little effort is required to keep it flowing.
During the Jewish Feast of Tabernacles, Jesus dramatically interrupted the temple ritual. He stood and cried out, “If anyone is thirsty, let Him come to Me and drink” (John 7:37). He described a simple process. Faith in Him is the basic condition for Him to quench our thirst. “He who believes in Me, as the Scripture said, ‘From his innermost being will flow rivers of living water.’” (John 7:38–39) Jesus goes beyond satisfying us; His life overflows. The Spirit in us bubbles out like a spring, forming rivers of living water that flow on to refresh other dusty, dry lives. Jesus might have alluded to any of several Scriptures that speak of the desert being watered.1 One passage even speaks of a coming king as a desert stream.2 In Jesus, Yahweh completed the supply of living water. Now it can overflow through us into the spiritually arid world to water others.3
Fountain of living water (waters) in Hebrew:
Meqor mayim khayyim
Strong’s Concordance numbers: 4726, 4325, 2416
Bible references: Jer. 2:13; 17:13
My people have committed two evils; they have forsaken me the fountain of living waters, and hewed them out cisterns, broken cisterns, that can hold no water. (Jeremiah 2:13 KJV)
Lord, you are the hope of Israel;
all who forsake you will be put to shame.
Those who turn away from you will be written in the dust
because they have forsaken the Lord,
the spring of living water. (Jeremiah 17:13 NIV)