What does John 4:23 mean by praying in spirit and truth?

John 4:23 actually says “worship in spirit and truth”.

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.  God is spirit, and those who worship him must worship in spirit and truth.”  John 4:23-24

Times were about to change.  The Old Covenant with the temple based worship and sacrificing of animals and regulations, was soon to pass away.  The New Covenant was soon to take over, where worship would be very different.  There would be no temple or synagogues.  There would be no tithing and sacrificing.   1 Peter 2:5:

you yourselves like living stones are being built up as a spiritual house, to be a holy priesthood, to offer spiritual sacrifices acceptable to God through Jesus Christ.

So all over the world, true believers are now worshiping God in spirit and truth. The Old Covenant has passed away and the New Covenant in Christ’s blood, unites God children.  Hebrews 12:27-29:

This phrase, “Yet once more,” indicates the removal of things that are shaken–that is, things that have been made–in order that the things that cannot be shaken may remain. Therefore let us be grateful for receiving a kingdom that cannot be shaken, and thus let us offer to God acceptable worship, with reverence and awe, for our God is a consuming fire.

Our walk and our worship is according to the spirit.  Romans 8:3-8

For God has done what the law, weakened by the flesh, could not do. By sending his own Son in the likeness of sinful flesh and for sin, he condemned sin in the flesh, in order that the righteous requirement of the law might be fulfilled in us, who walk not according to the flesh but according to the Spirit. For those who live according to the flesh set their minds on the things of the flesh, but those who live according to the Spirit set their minds on the things of the Spirit. For to set the mind on the flesh is death, but to set the mind on the Spirit is life and peace. For the mind that is set on the flesh is hostile to God, for it does not submit to God’s law; indeed, it cannot. Those who are in the flesh cannot please God.