The Greek noun chara (χαρά) means joy, gladness, or delight. It appears about 59 times in the NT and is closely related to charis (grace) — they share the same root. Joy is grace experienced and felt.
Chara is not happiness dependent on circumstances — it is the deep gladness rooted in the reality of God. The Annunciation angel declared 'great joy' (charan megalen, Luke 2:10). Jesus spoke of the Father's chara over one repentant sinner (Luke 15:7, 10). He told the disciples: 'I have told you this so that my joy may be in you and that your joy may be complete' (John 15:11) — Jesus' own joy transferred to believers. The fruit of the Spirit includes chara (Galatians 5:22). Paul commanded: 'Rejoice in the Lord always. I will say it again: Rejoice!' (Philippians 4:4) — written from prison. Hebrews 12:2 reveals the source of Jesus' endurance: 'for the joy (chara) set before him he endured the cross.' Joy is the fuel of the kingdom.