"But the hour cometh, and now is, when the true worshippers shall worship the Father in spirit and in truth: for the Father seeketh such to worship Him." John 4:23
In spirit and truth: When you are born again your spirit is made alive by God. Your spirit considers God and worships God in perfection. One of the battles in your life is finding the true balance of body, mind, spirit so that when you worship God you allow your true inner self, your spirit, to connect with God. When this happens worship is at its best.
Your spirit is always seeking life and alignment with God, while your body is quite often seeking other, less spiritual endeavors and the mind is trying to figure it all out. In the mind you do have some control. If you are a disciplined person you can manage your body better and give more place to your spirit. If you are not a disciplined person you will have continued difficulty with your body wanting and desiring things that are not good for it an you are much more likely to cave in and you will have more difficulty discerning your spiritual inclinations.
Don't think for one minute that if you are not born again but you have a very disciplined mind that somehow you can manage your spirit. You can better manage the body than if you are not disciplined, but you have no control over your spirit. Before you are born again your spirit is dormant, not functional, non-receptive, not connected to God. That's why Paul says in Romans 8:5-8, "For they that are after the flesh do mind the things of the flesh; but they that are after the Spirit the things of the Spirit. For to be carnally minded is death; but to be spiritually minded is life and peace. Because the carnal mind is enmity with God: for it is not subject to the law of God, neither indeed can be. So then they that are in the flesh cannot please God."
What does it mean to worship God in truth? It's real simple. You connect with God (worship) consciously revealing your whole self to God. The good, the bad, and the ugly. You come before God without trying to cover up who you are, what you have done, where you've been, what you believe or why you did what you did.
Now catch this: You can come to God by putting on a front and acting like someone you're not. You can put on a show for others as to how spiritual you are. You can live one way and present yourself another way at church. You can lie and cheat and steal and defraud others and as long as no one knows you can look spiritual , but that's not worship, that's religion. If you do that there is no connection to God, no spiritual awareness, no inspiration, no truth. God has had enough of that.
No, to worship God in spirit and truth, you will have to change business as usual. It's real likely you will have to unlearn a great many things before you come to the place where you are even true to yourself, much less true to God. Total revelation of your self to God might be the most freeing experience you have ever had. Are you willing to take a chance with God and let God in on all your secrets? He knows anyway. Why not enjoy the benefit of being honest with God?