Reading from the Synaxarion:

Joel the Prophet

The Prophet Joel, whose name means "Yah is God," was of the tribe of Reuben, the son of Bathuel, and lived from 810 to 750 B.C. (but some say in the 7th century B.C.). His book is divided into three chapters, and is the second in order of the minor Prophets. He foretold the coming of the Holy Spirit on the day of Pentecost (Joel 2:28, and quoted by the Apostle Peter in Acts 2:17), and the saving power of the Name of our Lord Jesus Christ (Joel 2:32).