An angel and a large collection of heavenly beings are singing praises to God in this verse. One group of shepherds was initially terrified by the appearance of the angel but was now thrilled. As these angels sing, they commemorate the birth of Jesus, who is now resting with Mary near Bethlehem. After the angelic choir departs, these shepherds will rush to Bethlehem to see the newborn Christ for themselves.
This good news that was announced by angels is available to anyone who believes in the Lord Jesus Christ. However, nowhere in Scripture does it state that there is peace on earth for everyone. Peace and favor from God are available only through faith in Christ alone. Justification by faith leads to peace with God. Men and women of goodwill are the only ones to be granted the peace of God on earth during Christ's millennial reign.
We must spread the good news of the gospel of grace to all who are opposing God. Christ has died for their sins and has risen from the dead. Those who believe in Him will not perish but will receive peace with God and the peace of God in their hearts. Upon His coming, peace on earth will be governed by righteousness forever.

Dear Heavenly Father, I know that without Jesus, there is nothing I could have done to warrant peace with You. My Lord, I thank You for giving me peace with You and receiving Your grace and goodwill in this age and in the ages to come as Your born-again child. Thank You for positioning me in Christ and clothing me in His righteousness so I can identify with Him, find favor in Your sight, and have peace in my heart. 
In Jesus's name I pray. Amen.