PSALM 23: A Song of David...

Even when clouds darken and all hope appears to be slipping from our grasp:

1A song of David. The Lord is my shepherd; I shall not want.		אמִזְמוֹר לְדָוִד יְהֹוָה רֹעִי לֹא אֶחְסָר:
A song of David: The Rabbis said: Wherever it says: “A song of David,” he would play [his musical instrument] and afterwards the Shechinah would rest on him. It is a song to bring the holy spirit upon David. And, wherever it says: “Of David, a song,” the Shechinah rested on him [first] and then he recited a song.
The Lord is my shepherd: In this desert where I am going, [therefore] I am confident that I will lack nothing.
2He causes me to lie down in green pastures; He leads me beside still waters.		בבִּנְאוֹת דֶּשֶׁא יַרְבִּיצֵנִי עַל מֵי מְנֻחוֹת יְנַהֲלֵנִי:
in green pasture: In grassy pastures. Since he commences to compare his sustenance to the pasture of an animal by saying, “The Lord is my shepherd”, “green pastures” is appropriate for the expression, “the Lord is my shepherd.” David recited this psalm in the forest of Hereth (I Sam. 22:5). Why was it called Hereth? Because it was as dry as a potsherd (חרס) and the Holy One, blessed be He, moistened it with the good of the world to come (Mid. Ps. 23:6).
3He restores my soul; He leads me in paths of righteousness for His name's sake.		גנַפְשִׁי יְשׁוֹבֵב יַנְחֵנִי בְמַעְגְּלֵי צֶדֶק לְמַעַן שְׁמוֹ:
He restores my soul: My spirit, which has been weakened by troubles and haste, He will restore to its previous status.
in paths of righteousness: In straight paths, so that I should not fall into the hands of my enemies.
4Even when I walk in the valley of darkness, I will fear no evil for You are with me; Your rod and Your staff-they comfort me.		דגַּם כִּי אֵלֵךְ בְּגֵיא צַלְמָוֶת לֹא אִירָא רָע כִּי אַתָּה עִמָּדִי שִׁבְטְךָ וּמִשְׁעַנְתֶּךָ הֵמָּה יְנַחֲמֻנִי:
in the valley of darkness: Heb. צלמות, in a land of darkness. He alludes to the desert of Ziph (I Sam. 23:13 28). Every [mention of] צלמות is an expression of darkness. Dunash ben Labrat defined it [in this manner].
Your rod and Your staff: The pains that came upon me, and the support, that I rely upon Your loving kindnessboth of them will comfort me, for they will serve to expiate my iniquity, and I am confident that You will set a table before me. That is the throne.
5You set a table before me in the presence of my adversaries; You anointed my head with oil; my cup overflows.		התַּעֲרֹךְ לְפָנַי | שֻׁלְחָן נֶגֶד צֹרְרָי דִּשַּׁנְתָּ בַשֶּׁמֶן רֹאשִׁי כּוֹסִי רְוָיָה:
You anointed my head with oil: I have already been anointed king by Your orders.
my cup overflows: Heb. רויה, an expression of fullness.
6May only goodness and kindness pursue me all the days of my life, and I will dwell in the house of the Lord for length of days.		ואַךְ טוֹב וָחֶסֶד יִרְדְּפוּנִי כָּל יְמֵי חַיָּי וְשַׁבְתִּי בְּבֵית יְהֹוָה לְאֹרֶךְ יָמִים:

Via: Chabad.