4 Av (the 5th of August), commemorates the beginning of the 52-day period in which Nehemiah rebuilt the walls of ancient Jerusalem. This period will finish on the 25th of ELUL. Nehemiah faced tremendous resistance returning to and rebuilding the city - no different today! So in this time, make an EXTRA EFFORT to advocate for Jerusalem, the Eternal Capital of the Jewish People and for G-d's House - a House of prayer for ALL nations. May we see the ancient and Eternal Jerusalem's be rebuilt in its full glory soon in our days.
On a personal level, this is an auspicious time to pray for your own "walls" - (may it be a lack of protection bodily [ie immune system, etc], physically, psychologically [lack of resolve against negative resistance] or spiritually, to be healed and restored. Use your personal prayers to also assist you to petition for the Shalom (wholeness) of Jerusalem.