What is worship?
There are many Biblical examples of worship including bowing down (Genesis 24-26), professing the truths of God (Matthew 14:33), Glorification (Psalm 29:2), falling on our faces (Revelation 11:16), and fasting and praying. (Luke 2:37). However, worship can be summed up pretty well in this one verse; "Therefore, I urge you, brothers and sisters, in view of God's mercy, to offer your bodies as a living sacrifice, holy and pleasing to God—this is your true and proper worship." (Romans 12:1)
According to my cute little pop up dictionary (Oxford American Dictionaries, incase it matters. :P), it is "The feeling or expression of reverence and adoration for a deity." I really like that definition, though I feel it'd be more accurate if they were to replace OR with AND.
According to John Piper in his book Desiring God,
Worship is a way of gladly reflecting back to God the radiance of His worth. It is not a mere act of willpower by which we perform outward acts. Without the engagement of the heart, we do not really worship. The engagement of the heart in worship is the coming alive of the feelings and emotions and affections of the heart. Where feelings for God are dead, worship is dead.
Isaiah 29:13 supports Piper's definition.
“And so the Lord says,
‘These people say they are mine.
They honor me with their lips,
but their hearts are far from me.
And their worship of me
is nothing but man-made rules learned by rote.’”
Bear in mind that Jesus quoted this verse to the religious leaders of His time. They LOOKED like "real" worshipers on the outside, but they weren't really worshiping. Worship is an outward expression of an inward feeling. Without the longing to see God and to follow Him wholly, our “worship” is nothing more than trite ritualism.
Why do we worship?
Biblical reasons for worshiping include these: He is good and His love endures forever (Psalm 100), He is Holy (Psalm 99:5), Jesus commands us to love God with all our heart, soul, mind and strength (Mark 12:30), In Him all things are created, and He is supreme (Colossians 1:16). And of course, because of His death and resurrection--His victory over sin (which I never got a specific reference for, because really the entire Bible is a testament to this. Without the resurrection the Bible loses its meaning).
The Bible is full of reasons why He deserves our worship, but worship must not be done out of duty. We need to wrap our heads around the idea that God not only DESERVES our worship, but He also DESIRES it and delights in it. Within the past five years of my life God has been increasing my desire to worship Him. It’s come to mean so much to me. It’s only recently that He’s begun showing me how much it means to Him. Worship is not about us. It’s the irrefutable recognition that we are His—that everything is His. I feel like realizing this is revolutionizing my view of worship. I've been like "Man, worship makes me feel so good", and now I'm excited to worship so I can bring HIM joy! Imagine that! The mighty, awesome God DESIRES our worship. worship is about Him. I want to make Him happy with my worship! :)
Why does God desire our worship?
He is a jealous God (Exodus 34:14). By the way, jealous has multiple definitions. My dictionary had one definition that was prefaced as being "of God". God's jealousy was defined in this way: "demanding faithfulness and exclusive worship”. Now, exclusive worship means YOU ARE NOT WORSHIPING ANYTHING ELSE. Most people think that's easy... like, "Oh, well, I don't pray to sun god Ra or Baal or nuttin' like dat so I'm good". But really, if worshiping is living our lives for something as defined in Romans, we can "worship" ANYTHING that we sacrifice our lives for! of course, it won't be true worship, nor will it be fulfilling. However, it will still separate you from Him. A servant cannot serve two masters.
Secondly, He loves us. The scriptures of God’s love for us are many (John 3:16, for instance), yet we cannot even put the perfection of His love into words. However, we can more clearly understand human love. Even in our imperfect love we desire love in return. God wants us to love Him. Our worship is a complete surrender to Him. What better way to prove you love Him than to surrender everything to Him? It is our true and proper worship (See Romans 12:1 again). After all, Jesus first surrendered everything for us.
We have a choice. We can choose to worship, or not to worship. However; dutiful, ritualistic worship is not really worship at all. When we choose to worship, we need to do it with joy and humility. We need to want to see Him. We need to realize that it’s all about Him and not about us. So shut your eyes, don’t think about the people around you, don’t think about yourself, and simply think about Him. Think of His perfect love, and that despite everything you’ve done, He still desires you to worship Him.
Man... God is amazing. :)