These are the words that Moses addressed to all Israel on the other side of the Jordan. - Deuteronomy 1:1
Tishah B'Av is a day of mourning the destruction of both ancient Temples in Jerusalem.
I pleaded with the Eternal at that time, saying, "O Eternal God, You who let Your servant see the first works of Your greatness and Your mighty hand, You whose powerful deeds no god in heaven or on earth can equal! Let me, I pray, cross over and see the good land on the other side of the Jordan, that good hill country, and the Lebanon." - Deuteronomy 3:23-25
And if you do obey these rules and observe them carefully, the Eternal your God will maintain faithfully for you the covenant made on oath with your fathers. - Deuteronomy 7:12
See, this day I set before you blessing and curse. - Deuteronomy 11:26