Prepare

In Joel 2:23-25, the prophet admonishes you and I to: "Put in the sickle and prepare for war!" This means it is time for the crops to be harvested, so put in the sickle and start working. Gather in the wheat, for the time of the Lord is at hand."

This means it is time to work, not rest.  It is time to reach those who do not know the Lord personally and speak to them about getting their heart right.  There is no time for lack or hesitance.  It is the time for harvest.

Secondly, He exhorts in Scripture that we must make preparation for war.  Anytime something good begins, the enemy tries to sneak in a destroy the work of your hand.  So be fully dressed in armor - be ready.  

What kind of armor are you wearing?  Prepare yourself.  For the moment that you begin gathering the harvest, the enemy will plan and strategize a surprise attack on you.  He will seek to discourage you and ruin your reputation.  He will place obstacles in your path to prevent you from doing the work of God.  But do not give in.  Prepare!