John 4:24 says "God is Spirit, and his worshipers must worship in the Spirit and in truth."
How do we know we are worshipping in Spirit and in truth?
πνευμα ο θεος και τους προσκυνουντας αυτον εν πνευματι και αληθεια δει προσκυνειν [TR]
(Stephanus 1550, Beza 1598, Elzevir 1624 and Scrivener 1894 are identical.)
The literal translation of this text is :
Spirit the God and they worshipping (it is a present participle and it is plural) must (singular) to worship (present infinitive) in spirit (no article) and truth (no article).
[The grammatical details I have taken from Bagster's Analytical Greek Lexicon. The translation is largely from the literal interlinear of the Englishman's Greek New Testament, but slightly altered for clarity.]
In the act of communal worshipping, each individual must worship in spirit (their own spirit) and in truth (not in a matter of 'the' truth, that is to say doctrine, but truly, in their own spirit).
[Note 'worshipping' is BrE ; 'worshiping' is AmE. Being a Brit, I use the former.]
My understanding of Jesus' words in this place is that it is a matter of sincerity.
It is possible to be among a company of worshipers and yet, oneself, to be insincere. One is not being true to one's own self, for there are matters not dealt with. There is sin not confessed. There is strife with others not resolved.
In other places Jesus makes it clear that one is to leave a gift at the altar, and to be reconciled to a brother. Only then is one fit to offer the gift.
Leave there thy gift before the altar, and go thy way; first be reconciled to thy brother, and then come and offer thy gift. [Matthew 5:24, KJV.]
If one has a guilty conscience (about anything) one is not fit to worship. For worship is in spirit. That is to say, it is within and from one's own spirit. If sin is present, then a sacrifice is required. Exodus, Leviticus and Deuteronomy teach us that, in detail. God cannot be approached unless one is doing so in righteousness.
The whole gospel is a matter of righteousness, for 'therein is the righteousness of God revealed' Romans 1:17. Only if God views me as justified, only if he looks upon me and sees righteousness, am I fit and ready, in spirit, to approach and worship him.
Even Shakespeare said 'This above all - to thine own self be true'. If I am insincere and not facing reality, God who is a Spirit will see my inward parts (into the very depths of my soul) and he will not accept the worship that is being hypocritically offered.
Given the actual words which Jesus has chosen, given the plural, the singular and the imperative which he employs, I understand that inward sincerity is the focus of his meaning.
As says James, the Apostle :
Draw nigh to God, and he will draw nigh to you. Cleanse your hands, ye sinners; and purify your hearts, ye double minded. [James 4:8, KJV.]
And we will know if we are true worshipers, if, when we draw near to God to worship, we meet God himself and we know his presence. Then are we assured that we have worshipped aright.
Looking at a larger section of the passage for context:
20 Our fathers worshiped on this mountain, but you say that in Jerusalem is the place where people ought to worship.” 21 Jesus said to her, “Woman, believe me, the hour is coming when neither on this mountain nor in Jerusalem will you worship the Father. 22 You worship what you do not know; we worship what we know, for salvation is from the Jews. 23 But the hour is coming, and is now here, when the true worshipers will worship the Father in spirit and truth, for the Father is seeking such people to worship him. 24 God is spirit, and those who worship him must worship in spirit and truth.” 25 The woman said to him, “I know that Messiah is coming (he who is called Christ). When he comes, he will tell us all things.” 26 Jesus said to her, “I who speak to you am he.”
When Jesus says"
24 God is spirit, and those who worship him must worship in spirit and truth.”
He is correcting the woman's misunderstanding that worship is tied to some specific place. Worship is our response from the heart to who God is and what He has done and it is not tied to a location. Worship is something that comes from the heart, the spirit and it is something that is true, or genuine.
true worshipers will worship the Father in spirit and truth
Another way to say it might be that the Children of God (genuine worshippers) respond to Him (worship) sincerely from the heart. A worship response might be song, prayer, awestruck silence, or a number of other possible responses.
"In Spirit" - I'm not saying this is the correct interpretive option, but one possibility is that it means the indwelling Spirit of God must dwell within the person.
However, you are not in the flesh but in the Spirit, if indeed the Spirit of God dwells in you. But if anyone does not have the Spirit of Christ, he does not belong to Him. Rom. 8:9 NASB
The Holy Spirit is given at the moment of faith/belief in the Jesus through the gospel.
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. JN 7:39 NASB
13 In Him, you also, after listening to the message of truth, the gospel of your salvation—having also believed, you were sealed in Him with the Holy Spirit of promise, 14 who is given as a pledge of our inheritance, with a view to the redemption of God’s own possession, to the praise of His glory. Eph 1:13-14 NASB
"in Truth" - one must come to God as He is, and not how they've imagined Him to be. Jesus' claims that God's word (the Bible) is true. This should be our number 1 source for information about who God is and what's He's like and should inform and direct our worship.
17 Sanctify them in the truth; Your word is truth. Jn 17:17 NASB
Example: If someone believes that if they sacrifice all of their worldly possessions and give them to the poor, goes to a certain church, gets buried in a certain location, takes communion, dies in a Holy war, that these actions cause God to owe them eternity, then they are mistaken. They do these actions in vain and not according to God's revealed truth.
For the Lord your God is the God of gods and the Lord of lords, the great, the mighty, and the awesome God who does not show partiality nor take a bribe. Deut 10:17
If one believes that all of their work required for their salvation was complete on the cross and they trust in Jesus' death and resurrection alone for the forgiveness of their sins they are worshiping God in Truth.
What does it mean to worship in truth and in Spirit
John 4:24 N (NASB)
24 "God is spirit, and those who worship Him must worship in spirit and truth.”
Worship In Truth.
Jesus said "Sanctify them in the truth; Your word is truth."(John 17:17 NASB) " Worship in truth" means to worship God in away acceptable to him , and in harmony with His will as revealed to us in his Word,the Bible . Such worship must not be based on theories ,hearsay, lies or human philosophies.
John 17:3 (NASB)
3 "This is eternal life, that they may know You, the only true God, and Jesus Christ whom You have sent."
May know You," from the Greek verb "ginosko"implies a continuous process of taking knowledge, getting personally acquainted with God, knowing his likes and dislikes, his moral values and standards.
Worship in Spirit.
God is a spirit, He is not material, he cannot be seen or felt and so those worshiping must worship in spirit. Such worship does not need to revolve around temples,or any other type of physical or visual form like statues and pictures ,(John 4:21-24) because Jesus words indicate that a true worshiper would be guided in his worship by the spirit of God.
The spirit examines, scrutinizes all things even the deep things of God, and guides our understanding of the scriptures. Paul wrote:
1 Corinthians 2:9-12 (NET Bible)
9" But just as it is written, “Things that no eye has seen, or ear heard, or mind imagined, are the things God has prepared for those who love him.” 10 God has revealed these to us by the Spirit. For the Spirit searches all things, even the deep things of God. 11 For who among men knows the things of a man except the man’s spirit within him? So too, no one knows the things of God except the Spirit of God. 12 Now we have not received the spirit of the world, but the Spirit who is from God, so that we may know the things that are freely given to us by God."
To "worship in truth " is to worship God in an acceptable way, as revealed to us in His Bible . To do so requires a conscientious and continuous effort to study the scriptures and so discern the likes and dislikes, the moral values and standards of God as well as His purpose for mankind. (John 17:3) By doing so , and harmonizing our life with the Bible truths , we show that we love God with all our heart, soul and mind. (Matthew 22:36-38)
To "worship in spirit" Is to be guided by God's spirit ,Paul wrote:
" The Spirit itself beareth witness with our spirit, that we are the children of God." ( Rom. 8:16 KJV)
The "Spirit itself" that is God's holy spirit must be attuned with "our spirit", that is our mental disposition that governs our emotions what to say and do, ( Compare Acts 17:16, John 11:33, 13:21, 2 Cor.2:13, Daniel 2:1, Psalm 142:3)and to "beareth witness" is to bring to our forgetful and imperfect mind, knowledge that we have previously acquired and forgot. Hence by bringing to our mind the inspired scriptures , we are guided to act in harmony with God will.Compare John 16:13 and John 4:24 CEV
John 16:13 (NASB)
13 "But when He, the Spirit of truth, comes, He will guide you into all the truth; for He will not speak on His own initiative, but whatever He hears, He will speak; and He will disclose to you what is to come."
John 4:24 Contemporary English Version
"God is Spirit, and those who worship God must be led by the Spirit to worship him according to the truth."
God is looking for people to come out of Babylon. 2 Corinthians 6:17 sums it up perfectly. Wherefore come out from amoung them, and be ye separate,saith the Lord, and touch not the unclean thing,and I will receive you.(unclean doctrines). Come out and away from false doctrine in this last and lukewarm generation. 2Timothy 2:15 Study to show thyself approved unto God, a workman that needeth not to be ashamed, rightly dividing the word of truth. It has to be spot on , correct. God is not into religion as such.But desires a very close relationship.Ephesians chapter 5 talks much on the topic.