The woman [then] said to Him, "Sir, [please] give me [some of] that water, so that I do not get thirsty [again], or have to come all the way here to draw [water]."
Jesus answered them, "Truly, truly, I tell you, you people are looking for me because you got to eat the loaves of bread and were satisfied and not because you saw [miraculous] signs. [See verse 14].
Just as you gave Him authority over all mankind, He will give never ending life to all those people [Note: The Greek word here is neuter gender, "all those things"] you have given Him.
For the wages for sinning is [spiritual] death, but God's free gift is never ending life in [fellowship with] Christ Jesus our Lord.
For those people who are [controlled] by the flesh think about [i.e., desire] what the flesh wants; but those who are [controlled] by the Holy Spirit [desire] what the Holy Spirit wants.
Now the natural person [Note: Since this person is contrasted with the spiritual person of verse 15, it is taken here to mean the person without the Holy Spirit] does not receive the things [i.e., truths] revealed by the Holy Spirit of God, because they are [considered] foolishness to him. And he cannot understand them because they must be discerned by using spiritual judgment [i.e., judgment aided by the Holy Spirit].
[When] you do ask, you do not receive it, because you ask from wrong motives, [just] so you can satisfy your own pleasures.
And [in addition], we know that the Son of God has come [in a physical body, See 4:2] and has given us understanding, so that we can know the True One [i.e., God], and that we are in [fellowship with] the True One, even His Son Jesus Christ. This Son is the true God and eternal life.