Gevurah (Omer)

לְךָ֣ יקוק הַגְּדֻלָּ֨ה וְהַגְּבוּרָ֤ה וְהַתִּפְאֶ֙רֶת֙ וְהַנֵּ֣צַח וְהַה֔וֹד כִּי־כֹ֖ל בַּשָּׁמַ֣יִם וּבָאָ֑רֶץ לְךָ֤ יקוק הַמַּמְלָכָ֔ה וְהַמִּתְנַשֵּׂ֖א לְכֹ֥ל ׀ לְרֹֽאשׁ׃

I Chronicles 29:11

Yours, LORD, are greatness, might, splendor, triumph, and majesty—yes, all that is in heaven and on earth; to You, LORD, belong kingship and preeminence above all.

משנה אבות ד׳:א׳

בֶּן זוֹמָא אוֹמֵר... אֵיזֶהוּ גִבּוֹר, הַכּוֹבֵשׁ אֶת יִצְרוֹ

Pirkei Avot 4:1

Ben Zoma said: ...Who is mighty? He who subdues his [evil] inclination

משלי ט״ז:ל״ב

ט֤וֹב אֶ֣רֶךְ אַ֭פַּיִם מִגִּבּ֑וֹר וּמֹשֵׁ֥ל בְּ֝רוּח֗וֹ מִלֹּכֵ֥ד עִֽיר׃

Proverbs 16:32

Better to be forbearing than mighty,
To have self-control than to conquer a city.

Here we see a direct link between Gevurah, strength and self-discipline. True strength is the ability to exercise restraint and self-control. As we step further into the wilderness and further from Egypt, we come closer to our true freedom. Freedom without structure quickly turns to chaos. Without taskmasters telling us what to do, we are empowered to make our own choices. What boundaries must we set for ourselves? How can we use good judgment without becoming judgmental?

ליקוטי מוהר"ן, תנינא א׳:י״ד:א׳

יד וּלְהִסְתַּכֵּל עַל עַצְמוֹ הֵיטֵב אִם הוּא רָאוּי לָזֶה לִשְׁפֹּט אֶת חֲבֵרוֹ, כִּי הַמִּשְׁפָּט לֵאלֹקִים הוּא, כִּי רַק הוּא יִתְבָּרַךְ לְבַדּוֹ רָאוּי לִשְׁפֹּט אֶת הָאָדָם, כְּמוֹ שֶׁאָמְרוּ רַבּוֹתֵינוּ זִכְרוֹנָם לִבְרָכָה (אבות פ"ב): אַל תָּדִין אֶת חֲבֵרְךָ עַד שֶׁתַּגִּיעַ לִמְקוֹמוֹ;

Likutei Moharan, Part II 1:14:1

14.A person... has to take a good look at himself and ask if he is fit to pass judgment on his fellow man. “For judgment belongs to God” (Deuteronomy 1:17). The Blessed One alone is fit to judge a person, as our Sages, of blessed memory, taught: Do not judge your fellow man until you have reached his place (Avot 2:4).

The Sefirah of Gevurah is also known as Din (Judgment). Unlike Chesed which is an outward, expansive sefirah, Gevurah is inward focused. Self-discipline, self-control, the ability to use good judgment in one's own decisions will bring someone true inner strength.
Sometimes our decisions do impact other people. When we are given power, how can we be sure to use it appropriately? What does it mean to set healthy boundaries for ourselves and with others?

שמואל ב כ״ג:ג׳

אָמַר֙ אֱלֹהֵ֣י יִשְׂרָאֵ֔ל לִ֥י דִבֶּ֖ר צ֣וּר יִשְׂרָאֵ֑ל מוֹשֵׁל֙ בָּאָדָ֔ם צַדִּ֕יק מוֹשֵׁ֖ל יִרְאַ֥ת אֱלֹהִֽים׃

II Samuel 23:3

The God of Israel has spoken,
The Rock of Israel said concerning me:
“He who rules men justly,
He who rules in awe of God

משלי ח׳:י״ג

יִ֥רְאַ֣ת יְהֹוָה֮ שְֽׂנֹ֫את־רָ֥ע גֵּ֘אָ֤ה וְגָא֨וֹן ׀ וְדֶ֣רֶךְ רָ֭ע וּפִ֨י תַהְפֻּכ֬וֹת שָׂנֵֽאתִי׃

Proverbs 8:13

To fear the LORD is to hate evil;
I hate pride, arrogance, the evil way,
And duplicity in speech.

According to this verse from II Samuel, to rule justly is to rule with Yirat Elokim (Awe or fear of God). In Proverbs, we see that this requires us to hate evil. To live with reverence or awe, we are also implored to place limits on the ego and be discerning in how we speak to others.
Gevurah is a demanding sefirah.
How can we exercise this spiritual muscle of discipline, awe, strength and judgment?

רש"י על בראשית א׳:א׳:ג׳

ברא אלהים וְלֹא נֶאֱמַר בָּרָא ה', שֶׁבַּתְּחִלָּה עָלָה בְמַחֲשָׁבָה לִבְרֹאתוֹ בְּמִדַּת הַדִּין, רָאָה שֶׁאֵין הָעוֹלָם מִתְקַיֵּם, הִקְדִּים מִדַּת רַחֲמִים וְשִׁתְּפָהּ לְמִהַ"דִּ, וְהַיְינוּ דִּכְתִיב בְּיוֹם עֲשׂוֹת ה' אֱלֹהִים אֶרֶץ וְשָׁמָיִם:

Rashi on Genesis 1:1:3

ברא אלהים GOD [AS JUDGE] CREATED — It does not state 'ברא ה “The Lord (the Merciful One) created, because at first God intended to create it (the world) to be placed under the attribute (rule) of strict justice, but He realised that the world could not thus endure and therefore gave precedence to Divine Mercy allying it with Divine Justice. It is to this that what is written in (Genesis 2:4) alludes — “In the day that the Lord God made earth and heaven”.

Questions For Further Self-Exploration Regarding Gevurah
Chesed in Gevurah (8)
When I judge or criticize another, am I doing so constructively and from a place of loving concern?
Gevurah in Gevurah (9)
Do I exercise the right amount of self-control? Am I too hard on myself? Am I too lenient? What can I do to improve my day-to-day decision making?
Tiferet in Gevurah (10)
Am I compassionate to others when they make decisions I disagree with? Am I compassionate to myself when I give in to temptations?
Netzah in Gevurah (11)
Is my discernment consistent? Do I follow through on my goals? Am I easily distracted?
Hod in Gevurah (12)
When I judge or criticize another, does it come from a place of pride or arrogance? Have I taken the time to consider their perspective or my own personal bias? Do I recognize God as the ultimate Judge?
Yesod in Gevurah (13)
Are the decisions I make going to have a positive impact on those with whom I feel connected (Friends, family, colleagues)?
Malchut in Gevurah (14)
Am I remembering to frame my good decisions and self-control in terms of my own autonomy? How are my decisions helping to actualize the best version of myself? How are my judgments helping (or hindering) others from being the best version of themselves?