As it is said, "Arise, complain aloud in the night, in the beginning of the watches" (Eichah 2:19); just as the HKB"H, laments at that moment, as it is written: "Hashem will cry aloud from on high, and from His holy habitation will he send forth His voice; He will cry very loudly over His habitation" (Yirmeyahu 25:30; and He then says: "Woe to my children on account of whose iniquity I destroyed My house and burnt My Temple, and them I exiled among the nations."
But if one is unable to rise at midnight, he shall at least make an effort to rise before dawn; as David HaMelech said: "I will wake up the morning-dawn" (Tehillim 57:9), which means I awaken the dawn, but the dawn does not awaken me.
One my perform the midnight ceremony even after midnight, and after that engage himself in the study of the Torah, everyone according to his knowledge. The study of a portion of the Mishnah is preferable to any other study, but if he is not so learned, he shall read Tehillim, Ma'amodot, or books of instruction. A little with devotion is better than much without devotion.
Rabbi Hiya taught: "The Ruach Hakodesh is in the presence of the one who studies the Torah at night; as it said: "Arise, complain aloud in the night, in the beginning of the watches; pour out like water your heart before the Face of Hashem." (Eichah 2:19); which means that the Ruach Hakodesh is then in your presence.
Our Rabbis, obm, said again: "He who engages in the study of the Torah at night is called 'a servant of Hashem' as it is said: 'All you servants of Hashem that stand in the house of Hashem in the night'" (Tehillim 134:1).
In the short nights, when it is impossible to rise so early, he shall at least try to rise early enough to have sufficient time within which to prepare himself to go to the Synagogue to pray together with the congregation. (Kitzur Shulchan Aruch, Laws Relating to the Conduct Upon Rising in the Morning)
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Translation:
Eichah - Lamenations
Yirmeyahu - Jeremiah
David HaMelech = King David
Ma'amodot - a compilation of readings from the Bible and Talmud
Tehillim - Psalms
Ruach Hakodesh - Divine Inspiration
obm - of blessed memory
