Very little is known about Joel. His name means Yahweh is God, which could indicate that he had pious parents. Nor can anyone be sure regarding what time he lived, although some internal references in his book indicate he ministered after the exile. In a sense it does not matter that we cannot pinpoint when he lived. After all, if God had wanted us to know he would have provided the information.
His book is best known for predicting the events of the Day of Pentecost, recorded in Acts 2. But it has other important lessons as well, including how we respond to adverse circumstances.
The first half of Chapter 1 describes the effects of a terrible plague of locusts. They were sent by God as a judgement on his people for their sins. One consequence of the devastation was that it was not possible to offer grain offerings in the temple. Every crop was devastated and everyone was affected.
The important detail to note is that it was the Lord who was in control of the locusts. Their arrival was not primarily caused by the natural turn of events. Instead the Lord had intervened and brought it about. Why?
The answer is given in the second half of the chapter. He sent the locusts in order to call his people to repentance. The repentance was to begin with the religious officials who were to call a National Assembly for the purpose of seeking the Lord. This gathering was a special occasion brought about by dire circumstances.
One of the obvious applications connects to this chapter is how we respond to sudden adverse circumstance in providence. Sometimes we are quick to acknowledge the sovereignty of God but slow to engage in repentance. This response suggests that we think the reason for the problem is connected to the sins of someone else.
Instead we should respond by thinking that we should repent as well. While our particular sins may not be as bad as someone else's, (but who are we to make that conclusion?), the fact of the matter is that each of our sins is disobedience to God and grieves the Spirit.
Repentance should be a prominent spiritual discipline in the lives of Christians, both personally and corporately. It should occur even when things are good. And it should definitely occur when sin is rampant, as it is today in our society.