Lord ... from everlasting to everlasting you are God
Isn't it difficult to think about what is everlasting? There never was a "time" when God wasn't there. So that means that the Bible word for everlasting, or eternal, (they mean the same) belong in the first place to God himself. Our Catechism tells us just what the Bible says: "God is a spirit — infinite eternal and unchangeable."
The Bible also tells us that God is pleased to share with us many of the great and good things which, because they come from him, are also everlasting. They come to us in and through God's own eternal Son, the Lord Jesus Christ.
For example, God promises eternal life to all who believe in Jesus. This life comes to us because Jesus carried our sins to his cross and died in our place. God made an eternal (everlasting) covenant of salvation through the blood Jesus shed — a covenant that God will never break with all who trust in Jesus for their salvation. It is everlasting. This means that Christians look forward to everlasting life in heaven — a life that begins here and now as we trust in Jesus — but in heaven the good things will keep getting better and better as we live there with Christ. However there are also everlasting bad thing for those who reject Jesus, and these bad things too will get worse and worse.
Lord, please help me to trust you and enjoy you for ever. Amen