John 4:13

Jesus answered and said unto her, Every one that drinketh this water shall thirst again; but whosoever drinketh of the water that I shall give him shall never thirst; but the water that I shall give him shall become in him a well of water springing up unto eternal life.

In this, Jesus defined the living water he promised as a spiritual power leading to eternal life. Such would satisfy the deepest thirst of the soul, and not merely for a time, but eternally. The source of such a blessing is uniquely in Jesus Christ; and it may not be earned or merited, but is a heavenly gift to fallen and sinful men. The gift, however, is conditional. The woman would not have given Jesus a drink of water unless he had asked it, nor would Christ have blessed her unless she had asked. The Lord will not endow any soul with living water unless that soul shall ask in the appointed way through compliance with conditions prerequisite to his blessing.

Eternal life ... here plainly identified the blessing Jesus promised the woman of Samaria. It was impossible after these words for the woman to have misunderstood the direction of our Lord's remarks. It does seem, however, that she misunderstood the promised blessing as including a cessation of ordinary thirst also, which would have made it unnecessary for her to come again to the well of water.