First Thessalonians 5:18 reads give thanks in all circumstances, for this is God's will for you in Christ Jesus. The words translated give thanks is from one word in the Greek. It is built from the word meaning grace. God owes us nothing and we owe Him everything! We deserve to have eternal condemnation, but He gives us eternal life and a multitude of good things we don’t deserve.
Thankfulness is to be all Inclusive - IN ALL CIRCUMSTANCES! It’s hard to give thanks when bad things happen but we are told to give thanks under every circumstance in life. Thankfulness is a Command - GIVE THANKS! God knew this would be a difficult thing to do that’s why he gave us this command. The commands of God are designed to help us break through the barriers that are unnatural and harmful to us.
Thankfulness is God’s Will - THIS IS GOD’S WILL FOR US! Being able to thank God in the circumstances is not just good advice. It is the will of God to thank Him in all circumstances even those that we do not like. Part of pleasing God is to do His will. When we don’t thank God for everything we move outside the will of God. Thankfulness is accomplished by our connection to Christ. It is IN CHRIST JESUS we can give thanks!