His name comes from the Hebrew "Chaggai" which translates "festive", and this also is the name of the prophetic book with his prophecies.
The prophet Haggai was a contemporary of Zechariah, son of Iddo, who prophesied with him and both helped the Governor Zerubbabel and Joshua the high priest in the rebuilding of the Temple in Jerusalem (Haggai 1.1; Zachary 1.1: Ezra 5.1-2; 6.14). There are no known details of the life of Haggai, but he lived in Jerusalem at the time of King Darius I of Persia, son of Hystaspes.. The five prophecies of his book were given in the 2nd year of that King – i.e. in 520 BC (See Haggai 1.1; 1.15; 2.1; 2.10; 2.20).
The book of Ezra shows how the Jewish people upon their return from captivity at the time of Cyrus II in 538 BC (2 Chronicles 36.22-23; Ezra 1.1-4) enthusiastically soon raised the altar and laid the foundations of the temple. But difficulties and opposition arose, and the work was stopped for some 16 years, the people having accommodated themselves not to proceed in the rebuilding of the temple on the grounds that the time had not come yet. Instead they dedicated themselves to building fine houses for their own use.
After this period, having removed the difficulties, the people still did not return to work on the temple, and so suffered a series of calamities (Haggai 1.6, 9-11; 2.15-17). Then prophet Haggai spoke five prophecies, which were transcribed in his book, making reproaches, giving encouragement, showing the reasons why God's blessings were not coming to them, and finally prophesying the destruction of the power of nations after the campaign of Armageddon (see HERE ) and the establishment of the power of the Messiah (the Millennium).
At first the people met the exhortations of the prophets, returning to work, but just after a month of working they were discouraged when older folk remembered the glory of the temple built by Solomon. Then a message from the Lord came through Haggai, saying "courage, because I am with you ... do not be afraid" (Haggai 2:1-9). The work then resumed and the temple was rebuilt in five years, and was ready in 515 BC (Ezra 5:1).
A month later, the Lord taught by means an illustration that consisted on the answer to two questions posed to priests, that is: a) if holy meat touched other food would it become holy? And b) if someone who was unclean because of a dead body touched any of those things, would it be unclean? The priests answered correctly “no” to the first and "yes" to the second. It meant that what is holy does not confer holiness to anything else, but what is contaminated communicates its filth. In other words, “work and worship do not sanctify sin, but sin infects work and worship”. This was a reminder to the people that their offerings to God were polluted and that they themselves were impure, while the temple was in ruins.
Before they started rebuilding the temple the people suffered shortages of wheat and wine, and their crops were spoilt with blight, mildew, and hail. Their endless delays in this work also brought the punishment of God in the form of a shortage of seed and fruit. But they would be blessed from that day on.
The fifth and final message comes soon after, and it is a prophecy that has not yet been fulfilled: it provides for the destruction of the power of nations and the establishment of the strength of the Messiah (the Millennium). Zerubbabel was of the lineage of David, from which the Messiah since came (Matthew 1.12 and Luke 3.27), and this explains the promise made to Zerubbabel, that he would be made a signet ring, representing the supreme authority of his Descendant.
See an outline of your book HERE .