It’s often important to assure despondent Christians that Jesus himself sometimes plumbed the emotional depths. But it’s equally important to guard against the opposite extreme, as if joy were a luxury we could well do without.
Being a man of sorrows was only one side of Jesus’ life. The Spirit dwelt in him without limit (John 3:34). This was not merely the anticipation of joy; it was the joy of anticipation—and it was a key element in the psychology of his obedience.
The Heart of Joy
Peter speaks of a similar joy when he describes believers as “greatly rejoicing” in anticipation of their final salvation (1 Peter 1:6). Indeed, joy is part of the spiritual profile of every Christian.
It has little to do, however, either with our natural temperament or with our personal circumstances. It is the fruit of the Spirit, and it is worth noting that when Paul uses that phrase, he speaks not of “fruits” in the plural, but of “fruit” in the singular. The fruit is one indivisible organic whole, which means that whenever the Spirit comes to live in a human soul the result is love and joy and peace, and all the other graces which the apostle mentions in Galatians 5:22–23. It is one fruit, with many segments. There cannot, therefore, not be joy in a Christian heart. Even its temporary absence is a symptom of some underlying spiritual malady.
On the other hand, the fruit is not produced mechanically, but grows up like the seed which germinated while the farmer slept (Mark 4:27). It is the result of a living relationship with the Holy Spirit. We bear it only if we keep in step with him.
When we grieve the Spirit, our own joy withers.
The Focus of Joy
But not only is the Spirit the one who personally produces this fruit in believers. He produces it by focusing our minds on spiritual things: those very things which the natural man cannot receive (1 Corinthians 2:14). Specifically, he fills our hearts with joy by focusing our minds not on joy itself, but on the majesty of God, the beauty of Christ and the unsearchable riches which are ours in him. Two or three examples must suffice.
First, the case of the Philippian jailer. Having received the gospel, he was filled with joy because he had come to believe in God (Acts 16:34). It’s not clear how narrowly we should take this (presumably in his previous life he had been an idolater, not an atheist), but whatever else is implied in the jailer’s coming to faith, it certainly meant that God had suddenly become utterly real to him—and commonplace though it is, there is no greater joy than the assurance that God is and is for you. To those who have come out of the dark night of atheism, this is the greatest truth of all. “It is a great thing to believe in God,” said the 17th-century Scottish theologian Robert Bruce. It makes the whole universe glow.
Secondly, there is the point which Peter makes in 1 Peter 1:8). The same is still true, surely, of believers today. The sheer beauty of his immaculate humanity and majestic deity captivates our hearts, and we draw our very identity from the fact that we are loved by God’s own Son.
Thirdly, we rejoice when we think of the future. Christ will return, and when he returns we will receive in full the inheritance already prepared for us in heaven. This is not something to be pushed to the margins of our Christian lives. It has to be absolutely central, as it was in the life of Christ, who in his closing hours focused his mind on the glory which would follow the completion of his work (John 17:1–5). If we bear in mind the close connection between hope and joy, what Peter is really saying is, “Be sure you are always ready to speak up whenever non-Christians ask you to explain the joy that so clearly fills your lives.”