The 5th of Tammuz is the date the prophet Ezekiel had his famous prophetic vision of the "Divine Chariot," which we read as the Haftorah portion on Shavuot and upon which certain areas of study in Kabbalah are based; Articles #1-2 discusses what was considered a prerequisite for prophecy.
Articles 4-7 present major mystical insights into different themes within the Weekly Reading,
while #3 is for the fifth chapter of Pirkei Avot, for those who continue to study it on Shabbat afternoons throughout the summer.

(Those of you in ISRAEL should click to 'Balak' for articles on your Weekly Reading.)