Though now you do not see Him, yet believing, you rejoice with joy inexpressible and full of glory.
1 Peter 1:8
Christians have many reasons for rejoicing. The primary one is based on who God is—He is sovereign. That is the single greatest truth about God. Nothing is outside His control, and He controls everything to work out ultimately for our good (Rom. 8:28). He has an infinite understanding of every aspect of our lives—where we are and what we say (Ps. 139:2–4). And He exercises His understanding in perfect wisdom. Knowing God like that should give us inexpressible and glorious joy.
We should also rejoice because God saved us, adopted us, and promised to give us an inheritance in Jesus Christ (Eph. 1:1–11). When Christ returns, we will enjoy His presence and the heavenly place prepared for us (John 14:2–3). Until then, we have joy in knowing God has promised to supply all our needs (Phil. 4:19). Furthermore, we have the privilege of serving the One we supremely love. That includes sharing the good news with the lost and encouraging fellow Christians to grow in their love and service for Him. We can also have joy in knowing we can pray to God at any time (Heb. 4:15–16).