By Rabbi A. Rothman
There are two customs when it comes to reciting Selichot.
According to Rabbi Yosef Karo, Jews begin reciting Selichot from the second day of Elul. Sephardic Jewry follows this custom. Rabbi Moshe Isserles, the "Rema," writes that the custom of the Ashkenazic Jews is to begin reciting them from the Sunday before Rosh HaShannah, on the condition that there remain at least four days of Selichot before Rosh Hashannah.
In any case, we begin reciting the Selichot on Sunday, or, more correctly, on Saturday night: If there remain more than four days between Saturday night and Rosh HaShannah - for example, where Rosh HaShannah falls on a Thursday or Sabbath - we begin reciting Selichot on the Saturday night closest to Rosh HaShannah; but, if there are fewer than four days separating Saturday night and Rosh HaShannah - for example, where Rosh HaShannah falls on a Monday or Tuesday - then we begin reciting Selichot on the preceding Saturday night.
The reason that we Ashkenazic Jews recite Selichot for at least four days before Rosh HaShannah is that there is a custom to observe ten days of fasting before Yom Kippur for the purpose of repentance. Since during the Ten Days of Repentance between Rosh HaShannah and Yom Kippur there are four days on which it is impossible to fast - i.e., the two days of Rosh HaShannah, one Sabbath, and Yom Kippur eve on which one is obliged to eat - four days are set aside before Rosh HaShannah for fasting.
This being the case, Selichot are recited on these days. Even though today most people do not actually fast on these ten days, it none the less remains customary to get up early for Selichot for at least ten days - i.e., the four days before Rosh HaShannah, and six days during the Ten Days of Repentance.
The best time for reciting Selichot is at "Ashmoret HaBoker" - i.e., the very end of the nighttime. At this time people are still asleep, and the world is peaceful and uncontaminated by evil thoughts and deeds. At this hour prayer issues from the depths of the heart, shatters all barriers, and is received in Heaven.
Most people, though, find it difficult to get up at such an early hour. Therefore, the accepted practice has become to rise for Selichot about an hour or a half-hour before morning prayers. Though it is no longer dark outside it is still permissible to recite Selichot. Hence, if a person feels that by rising early his work will suffer, it is preferable that he rise for Selichot a half-hour before the normal time.