“Then God spoke all these words, saying, “I am Yahweh your God, who brought you out of the land of Egypt, out of the house of slavery. “You shall have no other gods before Me. “You shall not make for yourself an idol, or any likeness of what is in heaven above or on the earth beneath or in the water under the earth. “You shall not worship them or serve them; for I, Yahweh your God, am a jealous God, visiting the iniquity of the fathers on the children, on the third and the fourth generations of those who hate Me, but showing lovingkindness to thousands, to those who love Me and keep My commandments.” (Exodus 20:1-6, LSB)

The inner essence of worship is
to know God truly
and then respond from the heart to that knowledge by
valuing God,
treasuring God,
prizing God,
enjoying God,
being satisfied with God above all earthly things.

And then that deep, restful, joyful satisfaction in God overflows in
demonstrable acts of praise from the lips and
demonstrable acts of love in serving others for the sake of Christ.

— John Piper, Definition of Worship

True worship is to feel in the heart and to express a humbling but delightful sense of admiration and astonished wonder and overwhelming love in the presence of that most ancient of mysteries, that unspeakable Majesty, which has been called by some the mysterium tremendum, and which the prophets called “the Lord our God.”

— A. W. Tozer, Authentic Worship, p. 21

True worship is not confined to what we do in church or open praise (although these things are both good, and we are told in the Bible to do them). True worship is the acknowledgment of God and all His power and glory in everything we do. The highest form of praise and worship is obedience to Him and His Word. To do this, we must know God; we cannot be ignorant of Him (Acts 17:23). Worship is to glorify and exalt God—to show our loyalty and admiration to our Father.
 — Got Questions, What is Worship

True worship is God-centered worship. People tend to get caught up in where they should worship, what music they should sing in worship, and how their worship looks to other people. Focusing on these things misses the point. Jesus tells us that true worshipers will worship God in spirit and in truth (John 4:24). This means we worship from the heart and the way God has designed. Worship can include praying, reading God’s Word with an open heart, singing, participating in communion, and serving others. It is not limited to one act, but is done properly when the heart and attitude of the person are in the right place.
— Got Questions, What is Worship

A Summary

1. Worship involves everything I say, do and think.
2. Worship involves the heart — we must love the Lord our God with all of our heart, soul, mind, and strength (Deuteronomy 6:5; 10:12; 11:13; 13:3; 30:6; Joshua 22:5; Matthew 22:37; Mark 12:33; Luke 10:27).
3. Worship involves truth — we must not worship that which is false or unreal — Exodus 20:1-6
4. Worship involves expression — we cannot hide or withhold our expressions of praise and adoration for all that God IS and all that He DOES.
5. Worship is NOT about ME — It is directed toward God and is done to bring Him glory. The best worship happens when I lose self-consciousness and get caught up in the contemplation of the Divine Majesty.
6. Worship is intensely personal and relational — We are in communion with our God and we sense His presence in our midst.
7. Worship is diverse — It is both individual and corporate, private and public, silent and vocal. It may or may not include instruments, is not limited to a particular place, does not require a certain style of music, and may or may not involve the raising of hands, clapping, or other postures. It may include all types of service to others.