Happy (μακάριος) is an attitude of enjoyment and delight, whereas Joy (χαρά) is contentment. In action, joy is rejoicing; however, it is different from exultation (ἀγαλλιάω), Matthew 5:12.
When the magi of the east saw the star of David rise, they knew the King of the Jews was born. They responded to this finding by rejoicing with very great joy because their discovery brought them happiness, Matthew 2:10. Zacharias is informed by an angel that the Lord has heard his supplication for a son. Elizabeth will bear him a boy, and he will have joy and gladness along with many others who will rejoice at his birth, Luke 1:14. In addressing the saints of Philippi, Paul expresses that they are his joy, Philippians 4:1. For they bring him a sense of delight just as the saints in Thessalonica, 1 Thessalonians 2:19, even though Paul has been separated from them through the persecution he was facing. Not only did they receive the gospel of the Christ, but they also took hold of eternal life through obedience to the gospel. During Christ’s ministry, as He proclaimed the gospel of the Kingdom of the Heavens, some of the Jews immediately received the message with joy; however, they were like seeds on stony ground that have no root, so they only endure for a short time, Matthew 4:16. Joy is not emotionally centered because it is also shown by the spirit beings, who do not possess a soul. There is great joy in heaven over one sinner changing his mind, Luke 15:7.
Unlike joy, which is often expressed in rejoicing because of satisfaction, happy is more of a state of mind. Happy is the man to whom the Lord does not impute sin, Romans 4:8. During the Sermon on the Mount when Jesus was speaking to the Jews about His coming kingdom, He expressed many reasons for them to be happy, even when facing persecution and being forced out into the wilderness by the Gentiles and the man of lawlessness. Happy are those who lack knowledge concerning what is happening in Jerusalem and to the temple, Matthew 5:3. Happy are those who mourn because they have hope of being comforted, Matthew 5:4. The Jews that maintain an objectivity of mind, hunger and thirst after righteousness, show mercy, have a pure heart, and are reviled because of Christ, while they await the return of the Messiah to deliver them, can be happy because they will inherit the earth, be filled, obtain mercy, see God, and be called the sons of God, Matthew 5:5-11.
The Christian has a happy hope that comes from knowing that the Lord will return, Titus 2:13. Happiness is a characteristic of God, for He is a happy Being, 1 Timothy 6:15. Joy is an aspect of the character of Christ, seen in the fruit from the Spirit, Galatians 5:22. When a Christian is Spiritual, emanating the things from the Spirit, he will be able to use this fruit, which will result in a sense of contentment in any situation. For we should learn to be satisfied with what we have and not be covetous, Hebrews 13:5.
Happiness is a state of mind that comes from a sense of well-being. Joy comes from experiencing a situation that turns out in a beneficial way, even when the circumstances are not ideal. Both happiness and joy are logical in nature, not emotional. Therefore, we can be happy and have joy even when facing negative circumstances because of the sense of well-being that comes from knowing that God will never leave us or forsake us.