In Devarim, the Parsha we read before Tisha B'Av Moshe Rabbeinu speaks about setting up Shoftim and Shotrim and the qualities one needs to be a judge in order to be a righteous judge. Moshe Rabbeinu, the ultimate in leadership says its too hard a burden to carry on his own.
Devarim 1:12-18
https://www.chabad.org/library/bible_cdo/aid/9965/jewish/Chapter-1.htm
12 How can I bear your trouble, your burden, and your strife all by myself? יב אֵיכָ֥ה אֶשָּׂ֖א לְבַדִּ֑י טָרְחֲכֶ֥ם וּמַשַּֽׂאֲכֶ֖ם וְרִֽיבְכֶֽם:
13Prepare for yourselves wise and understanding men, known among your tribes, and I will make them heads over you. יג הָב֣וּ לָ֠כֶ֠ם אֲנָשִׁ֨ים חֲכָמִ֧ים וּנְבֹנִ֛ים וִֽידֻעִ֖ים לְשִׁבְטֵיכֶ֑ם וַֽאֲשִׂימֵ֖ם בְּרָֽאשֵׁיכֶֽם:
14 And you answered me and said, 'The thing you have spoken is good for us to do.' יד וַתַּֽעֲנ֖וּ אֹתִ֑י וַתֹּ֣אמְר֔וּ טוֹב־הַדָּבָ֥ר אֲשֶׁר־דִּבַּ֖רְתָּ לַֽעֲשֽׂוֹת:
15 So I took the heads of your tribes, men wise and well known, and I made them heads over you, leaders over thousands, leaders over hundreds, leaders over fifties, and leaders over tens, and officers, over your tribes. טו וָֽאֶקַּ֞ח אֶת־רָאשֵׁ֣י שִׁבְטֵיכֶ֗ם אֲנָשִׁ֤ים חֲכָמִים֙ וִֽידֻעִ֔ים וָֽאֶתֵּ֥ן אוֹתָ֛ם רָאשִׁ֖ים עֲלֵיכֶ֑ם שָׂרֵ֨י אֲלָפִ֜ים וְשָׂרֵ֣י מֵא֗וֹת וְשָׂרֵ֤י חֲמִשִּׁים֙ וְשָׂרֵ֣י עֲשָׂרֹ֔ת וְשֹֽׁטְרִ֖ים לְשִׁבְטֵיכֶֽם:
16And I commanded your judges at that time, saying, "Hear [disputes] between your brothers and judge justly between a man and his brother, and between his litigant. טז וָֽאֲצַוֶּה֙ אֶת־שֹׁ֣פְטֵיכֶ֔ם בָּעֵ֥ת הַהִ֖וא לֵאמֹ֑ר שָׁמֹ֤עַ בֵּֽין־אֲחֵיכֶם֙ וּשְׁפַטְתֶּ֣ם צֶ֔דֶק בֵּֽין־אִ֥ישׁ וּבֵֽין־אָחִ֖יו וּבֵ֥ין גֵּרֽוֹ:
17 You shall not favor persons in judgment; [rather] you shall hear the small just as the great; you shall not fear any man, for the judgment is upon the Lord, and the case that is too difficult for you, bring to me, and I will hear it." יז לֹֽא־תַכִּ֨ירוּ פָנִ֜ים בַּמִּשְׁפָּ֗ט כַּקָּטֹ֤ן כַּגָּדֹל֙ תִּשְׁמָע֔וּן לֹ֤א תָג֨וּרוּ֙ מִפְּנֵי־אִ֔ישׁ כִּ֥י הַמִּשְׁפָּ֖ט לֵֽאלֹהִ֣ים ה֑וּא וְהַדָּבָר֙ אֲשֶׁ֣ר יִקְשֶׁ֣ה מִכֶּ֔ם תַּקְרִב֥וּן אֵלַ֖י וּשְׁמַעְתִּֽיו:
18 And I commanded you at that time all the things you should do. יח וָֽאֲצַוֶּ֥ה אֶתְכֶ֖ם בָּעֵ֣ת הַהִ֑וא אֵ֥ת כָּל־הַדְּבָרִ֖ים אֲשֶׁ֥ר תַּֽעֲשֽׂוּן:
The Haftorah of the 2nd Shabbat of the 3 weeks, bein Hametzarim ends with
ירמיהו, 4:1 https://www.chabad.org/library/bible_cdo/aid/16001/jewish/Chapter-4.htm
1 If you return, O Israel, says the Lord, to Me, you shall return, and if you remove your detestable things from My Presence, you shall not wander. א אִם־תָּשׁ֨וּב יִשְׂרָאֵ֧ל | נְאֻם־יְהֹוָ֛ה אֵלַ֖י תָּשׁ֑וּב וְאִם־תָּסִ֧יר שִׁקּוּצֶ֛יךָ מִפָּנַ֖י וְלֹ֥א תָנֽוּד:
2 And you will swear, "As the Lord lives," in truth and in justice and in righteousness, nations will bless themselves with him and boast about him. ב וְנִשְׁבַּ֙עְתָּ֙ חַי־יְהֹוָ֔ה בֶּאֱמֶ֖ת בְּמִשְׁפָּ֣ט וּבִצְדָקָ֑ה וְהִתְבָּ֥רְכוּ ב֛וֹ
The entire Haftora of Sefer Devarim, Isaiah Chapter 1, Shabbath Chazon, read before Tisha B'Av focuses on that theme. The Haftorah ends:
https://www.chabad.org/library/bible_cdo/aid/15932/jewish/Chapter-1.htm
26 And I will restore your judges as at first and your counsellors as in the beginning; afterwards you shall be called City of Righteousness, Faithful City. כו וְאָשִׁ֚יבָה שֹֽׁפְטַ֙יִךְ֙ כְּבָרִ֣אשֹׁנָ֔ה וְיֹֽעֲצַ֖יִךְ כְּבַתְּחִלָּ֑ה אַֽחֲרֵי־כֵ֗ן יִקָּ֚רֵא לָךְ֙ עִ֣יר הַצֶּ֔דֶק קִרְיָ֖ה נֶֽאֱמָּנָֽה:
27 Zion shall be redeemed through justice and her penitent through righteousness. כז צִיּ֖וֹן בְּמִשְׁפָּ֣ט תִּפָּדֶ֑ה וְשָׁבֶ֖יהָ בִּצְדָקָֽה
The Torah reading on Tisha b'Av itself ends with a focus on Mitzvos Hashem
https://www.chabad.org/library/bible_cdo/aid/9968/jewish/Chapter-4.htm
Devarim 4
39 And you shall know this day and consider it in your heart, that the Lord He is God in heaven above, and upon the earth below; there is none else. לט וְיָֽדַעְתָּ֣ הַיּ֗וֹם וַֽהֲשֵֽׁבֹתָ֘ אֶל־לְבָבֶ֒ךָ֒ כִּ֤י יְהֹוָה֙ ה֣וּא הָֽאֱלֹהִ֔ים בַּשָּׁמַ֣יִם מִמַּ֔עַל וְעַל־הָאָ֖רֶץ מִתָּ֑חַת אֵ֖ין עֽוֹד:
40 And you shall observe His statutes and His commandments, which I command you this day, that it may be well with you and your children after you, and that you may prolong your days upon the earth which the Lord your God gives you forever. מ וְשָֽׁמַרְתָּ֞ אֶת־חֻקָּ֣יו וְאֶת־מִצְוֹתָ֗יו אֲשֶׁ֨ר אָֽנֹכִ֤י מְצַוְּךָ֙ הַיּ֔וֹם אֲשֶׁר֙ יִיטַ֣ב לְךָ֔ וּלְבָנֶ֖יךָ אַֽחֲרֶ֑יךָ וּלְמַ֨עַן תַּֽאֲרִ֤יךְ יָמִים֙ עַל־הָ֣אֲדָמָ֔ה אֲשֶׁ֨ר יְהֹוָ֧ה אֱלֹהֶ֛יךָ נֹתֵ֥ן לְךָ֖ כָּל־הַיָּמִֽים:
And the Haftorah read on Tisha Baav also ends with emulating Hashem and Knowing Hashem, a G-d who practices kindness, justice and righteousness and in this we we understand and know Him.
https://www.chabad.org/library/bible_cdo/aid/16006/jewish/Chapter-9.htm
22 Thus says the Lord: Let not the wise man boast of his wisdom, nor the strong man boast of his strength, nor the rich man boast of his riches. כב כֹּ֣ה | אָמַ֣ר יְהֹוָ֗ה אַל־יִתְהַלֵּ֚ל חָכָם֙ בְּחָכְמָת֔וֹ וְאַל־יִתְהַלֵּ֥ל הַגִּבּ֖וֹר בִּגְבֽוּרָת֑וֹ אַל־יִתְהַלֵּ֥ל עָשִׁ֖יר בְּעָשְׁרֽוֹ:
23 But let him that boasts exult in this, that he understands and knows me, for I am the Lord Who practices kindness, justice and righteousness on the earth; for in these things I delight, says the Lord. כג כִּ֣י אִם־בְּזֹ֞את יִתְהַלֵּ֣ל הַמִּתְהַלֵּ֗ל הַשְׂכֵּל֘ וְיָדֹ֣עַ אוֹתִי֒ כִּי אֲנִ֣י יְהֹוָ֔ה עֹ֥שֶׂה חֶ֛סֶד מִשְׁפָּ֥ט וּצְדָקָ֖ה בָּאָ֑רֶץ כִּֽי־בְאֵ֥לֶּה חָפַ֖צְתִּי נְאֻם־יְהֹוָֽה:
The prayer that men say when they put on Tefillin taken from the prophet Hoshea who prophesized prior to the destruction of the temple, speaks about a future redemption and being betrothed to Hashem.
Hosea 2:21–22.
כא וְאֵרַשְׂתִּיךְ לִי, לְעוֹלָם; וְאֵרַשְׂתִּיךְ לִי בְּצֶדֶק וּבְמִשְׁפָּט, וּבְחֶסֶד וּבְרַחֲמִים. כב וְאֵרַשְׂתִּיךְ לִי, בֶּאֱמוּנָה; וְיָדַעַתְּ, אֶת-יְהוָה.
אמר רבי יוחנן: ענוותנותו של רבי זכריה בן אבקולס, החריבה את ביתנו, ושרפה את היכלנו, והגליתנו מארצנו!
במדרש רבה
...אמר לו (המארח לבר קמצא) קום לך, לקחו בידו והוציאו, והיה שם רבי זכריה בן אבקולס, והיה סיפק בידו למחות ולא מיחה..."
Why were all the army age men in the Desert, the Midbar, also punished for Chait HaMiraglim the Sin of the Spies so that they too had to die out in the desert?