Psalm 27: "L'David ha-Shem Ori"
(א) לְדָוִ֨ד ׀ יְהֹוָ֤ה ׀ אוֹרִ֣י וְ֭יִשְׁעִי מִמִּ֣י אִירָ֑א יְהֹוָ֥ה מָעוֹז־חַ֝יַּ֗י מִמִּ֥י אֶפְחָֽד׃

(1) Of David. The LORD is my light and my help; whom should I fear? The LORD is the stronghold of my life, whom should I dread?

Coat of arms of Oxford University, with passage from Psalm 27 as motto:

"Dominus illuminatio mea," "The Lord is my light."

(ד) רַבָּנָן פָּתְרִין קְרָא בְּרֹאשׁ הַשָּׁנָה וְיוֹם הַכִּפּוּרִים, אוֹרִי בְּרֹאשׁ הַשָּׁנָה וְיִשְׁעִי בְּיוֹם הַכִּפּוּרִים,

The first Chassidic Siddur, written by R.Shabtai Rashkov (1655-1745), pupil of the Baal Shem Tov, cites Psalm 27:1 and this midrash as the inspiration for the recitation of Psalm 27 during the Tishrei holidays. This is the source for this practice.

(א) לְדָוִ֨ד ׀

יְהֹוָ֤ה׀ אוֹרִ֣י וְ֭יִשְׁעִי מִמִּ֣י אִירָ֑א יְהֹוָ֥ה מָעוֹז־חַ֝יַּ֗י מִמִּ֥י אֶפְחָֽד׃ (ב) בִּקְרֹ֤ב עָלַ֨י ׀ מְרֵעִים֮ לֶאֱכֹ֢ל אֶת־בְּשָׂ֫רִ֥י צָרַ֣י וְאֹיְבַ֣י לִ֑י הֵ֖מָּה כָשְׁל֣וּ וְנָפָֽלוּ׃ (ג) אִם־תַּחֲנֶ֬ה עָלַ֨י ׀ מַחֲנֶה֮ לֹא־יִירָ֢א לִ֫בִּ֥י אִם־תָּק֣וּם עָ֭לַי מִלְחָמָ֑ה בְּ֝זֹ֗את אֲנִ֣י בוֹטֵֽחַ׃

(ד) אַחַ֤ת ׀ שָׁאַ֣לְתִּי מֵֽאֵת־יְהֹוָה֮ אוֹתָ֢הּ אֲבַ֫קֵּ֥שׁ שִׁבְתִּ֣י בְּבֵית־יְ֭הֹוָה כׇּל־יְמֵ֣י חַיַּ֑י לַחֲז֥וֹת בְּנֹעַם־יְ֝הֹוָ֗ה וּלְבַקֵּ֥ר בְּהֵֽיכָלֽוֹ׃ (ה) כִּ֤י יִצְפְּנֵ֨נִי ׀ בְּסֻכֹּה֮ בְּי֢וֹם רָ֫עָ֥ה יַ֭סְתִּרֵנִי בְּסֵ֣תֶר אׇהֳל֑וֹ בְּ֝צ֗וּר יְרוֹמְמֵֽנִי׃ (ו) וְעַתָּ֨ה יָר֪וּם רֹאשִׁ֡י עַ֤ל אֹיְבַ֬י סְֽבִיבוֹתַ֗י וְאֶזְבְּחָ֣ה בְ֭אׇהֳלוֹ זִבְחֵ֣י תְרוּעָ֑ה אָשִׁ֥ירָה וַ֝אֲזַמְּרָ֗ה לַֽיהֹוָֽה׃

(ז) שְׁמַע־יְהֹוָ֖ה קוֹלִ֥י אֶקְרָ֗א וְחׇנֵּ֥נִי וַֽעֲנֵֽנִי׃

(ח) לְךָ֤ ׀ אָמַ֣ר לִ֭בִּי בַּקְּשׁ֣וּ פָנָ֑י אֶת־פָּנֶ֖יךָ יְהֹוָ֣ה אֲבַקֵּֽשׁ׃ (ט) אַל־תַּסְתֵּ֬ר פָּנֶ֨יךָ ׀ מִמֶּנִּי֮ אַ֥ל תַּט־בְּאַ֗ף עַ֫בְדֶּ֥ךָ עֶזְרָתִ֥י הָיִ֑יתָ אַֽל־תִּטְּשֵׁ֥נִי וְאַל־תַּ֝עַזְבֵ֗נִי אֱלֹהֵ֥י יִשְׁעִֽי׃ (י) כִּֽי־אָבִ֣י וְאִמִּ֣י עֲזָב֑וּנִי וַֽיהֹוָ֣ה יַאַסְפֵֽנִי׃ (יא) ה֤וֹרֵ֥נִי יְהֹוָ֗ה דַּ֫רְכֶּ֥ךָ וּ֭נְחֵנִי בְּאֹ֣רַח מִישׁ֑וֹר לְ֝מַ֗עַן שֽׁוֹרְרָֽי׃ (יב) אַֽל־תִּ֭תְּנֵנִי בְּנֶ֣פֶשׁ צָרָ֑י כִּ֥י קָמוּ־בִ֥י עֵדֵי־שֶׁ֝֗קֶר וִיפֵ֥חַ חָמָֽס׃

יג) לׅׄוּׅׄלֵׅ֗ׄאׅׄ הֶ֭אֱמַנְתִּי לִרְא֥וֹת בְּֽטוּב־יְהֹוָ֗ה בְּאֶ֣רֶץ חַיִּֽים׃....

(יד) קַוֵּ֗ה אֶל־יְ֫הֹוָ֥ה חֲ֭זַק וְיַאֲמֵ֣ץ לִבֶּ֑ךָ וְ֝קַוֵּ֗ה אֶל־יְהֹוָֽה׃ {פ}

(1) Of David.

The LORD is my light and my help; whom should I fear? The LORD is the stronghold of my life, whom should I dread? (2) When evil men assail me to devour my flesh— it is they, my foes and my enemies, who stumble and fall. (3) Should an army besiege me, my heart would have no fear; should war beset me, still would I be confident.

(4) One thing I ask of the LORD, only that do I seek: to live in the house of the LORD all the days of my life, to gaze upon the beauty of the LORD, to frequent His temple. (5) He will shelter me in His pavilion on an evil day, grant me the protection of His tent, raise me high upon a rock. (6) Now is my head high over my enemies roundabout; I sacrifice in His tent with shouts of joy, singing and chanting a hymn to the LORD.

(7) Hear, O LORD, when I cry aloud; have mercy on me, answer me. (8) In Your behalf my heart says: “Seek My face!” O LORD, I seek Your face. (9) Do not hide Your face from me; do not thrust aside Your servant in anger; You have ever been my help. Do not forsake me, do not abandon me, O God, my deliverer. (10) Though my father and mother abandon me, the LORD will take me in. (11) Show me Your way, O LORD, and lead me on a level path because of my watchful foes. (12) Do not subject me to the will of my foes, for false witnesses and unjust accusers have appeared against me.

(13) Had I not the assurance that I would enjoy the goodness of the LORD in the land of the living….

(14) Look to the LORD; be strong and of good courage! O look to the LORD!

Re verse 10 see Isaiah below:

(י) כִּֽי־אָבִ֣י וְאִמִּ֣י עֲזָב֑וּנִי וַֽיהֹוָ֣ה יַאַסְפֵֽנִי׃

(10) Though my father and mother abandon me, the LORD will take me in.

(טו) הֲתִשְׁכַּ֤ח אִשָּׁה֙ עוּלָ֔הּ מֵרַחֵ֖ם בֶּן־בִּטְנָ֑הּ גַּם־אֵ֣לֶּה תִשְׁכַּ֔חְנָה וְאָנֹכִ֖י לֹ֥א אֶשְׁכָּחֵֽךְ׃

(15) Can a woman forget her baby, Or disown the child of her womb? Though she might forget, I never could forget you.

אם - גם אם תחנה עלי מחנה - שהם מהגוים ואם הם רבים ואם הצרכתי לבא למלחמה עמהם, בזאת והטעם: שהשם אורי וישעי.
ויש אומרים: כי בזאת – היא השאלה הנזכרת אחר כן.

(יג) לׅׄוּׅׄלֵׅ֗ׄאׅׄ הֶ֭אֱמַנְתִּי לִרְא֥וֹת בְּֽטוּב־יְהֹוָ֗ה בְּאֶ֣רֶץ חַיִּֽים׃

(13) Had I not the assurance that I would enjoy the goodness of the LORD in the land of the living…

לולא האמנתי וגו'. אם לא שהאמנתי בהקב"ה כבר קמו בי אותם עדי שקר וכלוני, לולא נקוד עליו למדרש שדרשו רבותינו יודע אני שאתה נותן שכר לצדיקים לעולם הבא אבל איני יודע אם יש לי חלק עמהם אם לאו:

Had I not believed in seeing, etc. If I had not believed in the Holy One, blessed be He, those false witnesses would have already risen against me and destroyed me. [The word] לולא is punctuated for the homily which our Sages expounded (Ber. 4a): I know that You give reward to the righteous in the world to come, but I do not know whether I have a share with them or not.

Metzudat David - by Rabbi David Altschuler, Prague, 1687-1769

לולא. כאומר הנה כמעט היו מאבדים אותי אם לא עמדה לי זכות האמנה שהאמנתי בדבר ה׳‎ אשר הבטיחני לראות בטובו בזה העולם:

In verse 13, the author indicates that were it not for the assurance of future reward, he would.... An ellipsis follows, with no final comment. The verse does not openly affirm the author's trust in the Almighty. Does this incomplete verse hint that his trust in God has been challenged, weakened?

Verse 14 adds a positive note with which the psalm concludes.

Note that there are dots above and below three letters in the first word, which usually suggests that one can read the word without these letters.

If we remove the 3 letters from the word, it is converted to a positive statement, affirming the author's trust in God:

(13) [I ] Had (I not) the assurance that I would enjoy the goodness of the LORD in the land of the living….

This amendation changes the entire meaning of the psalm.