Philippians 4:4 says "Rejoice in the Lord always. I will say it again: Rejoice!"
2020 has been a challenging year for the world. The COVID-19 Pandemic has left our lives wishing this year would hurry and leave. The key to getting through this and any difficult situation is to have joy or to be cheerful. It is amazing that so many people of God express limited joy even when times call for happiness. When we rejoice or are cheerful, our joy is centered on the Lord. Because we are in Christ it allows us to look on the bright side, no matter what we encounter. We have a personal advantage to having continuous joy.
First, It is a necessity if you are serving others, for God loves a cheerful giver. How can you assist someone else, teach someone or share with someone if you are sour? Second, we have joy because Christ has died for our sins, something we could not do for ourselves. Third, we are happy when we meet with fellow saints and share the wonderful testimonies of what God has done in our lives. Lastly when we achieve levels of success for the kingdom, it is a gratifying feeling, for we have moved one step closer to the plan that God has designed for our lives.
Notice that Paul emphasizes again to rejoice, for when times are tough and it seems we won't make it through, rejoice. He impresses upon us that whatever else you forget, remember this: Be sure to rejoice.