This verse instructs us to serve the Lord with gladness and come before Him with joyful songs. He is our Creator and deserves our praise and worship. He has been good to us and has shown us His steadfast love. We can approach Him with confidence, knowing that He is our faithful God. Let us show our gratitude by giving Him the reverence He deserves and celebrating His goodness in our lives. 
In Psalm 100, the Lord is praised in a beautiful way, and is often affectionately referred to as the "Old Hundredth". This message calls upon every people and tribe, nation, language, and race of the world to join together as one, in worshipful thanksgiving and exultant praise to our Almighty God. He is worthy of all honor and praise, now and forevermore.
The exciting theme that threads its way throughout the entire Bible is joining together as one in joyful psalms of celebration, and lifting up our voices together in spiritual songs and harmonious hymns of praise. Our Almighty God loves us so much that He gave His only begotten Son so that whoever believes in Him should not perish, but live forever.

Dear Heavenly Father,  I come to You today with gladness in my heart and a joyful song on my lips. You are my Creator and I give You all my praise and worship. You have been so good to me and Your steadfast love endures forever. I approach You with confidence, knowing that You are a faithful God. I give You the reverence You deserve and celebrate Your goodness in my life. You are worthy of all honor and praise, now and always. 
In Jesus's name I pray. Amen.