It is brought down in the Imrei Pinchas (445) that "Rebbe Pinchas of Koritz zt’l was very machmir to tovel on the first day of selichos, early in the morning, and on erev Rosh Hashanah, early in the morning, and on the two days of Rosh Hashanah... Although he was lenient [with mikvah], he was more stringent with the tevilos these days."
Reb Yaakov Landau zt’l, rav of Bnei Brak, generally contained his emotions. On the first night of selichos, he was the chazan. When he began Ashrei, his voice didn't show any emotion, but when he came to תהילת 'ה, he cried copiously and continued to cry throughout the selichos. It was almost impossible to hear his voice through his cries.
Once, before selichos, Rebbe Aharon of Belz zt’l told the chazan, "Hoych! Hoych! Daven loudly because this will rouse the community to say selichos with kavanah and hislahavus. "Don't be afraid of becoming hoarse because others can take your place."
Someone asked Reb Yosef Chaim Sonnenfeld zt'l, "I'm a melamed, and Shulchan Aruch (Yorah Deah 245:17) states that a melamed must sleep well. Perhaps I shouldn't go to selichos because that would cause me not to get enough sleep."
Reb Yosef Chaim Sonnenfeld replied, "I don't see any heter for you not to wake up for selichos."
Leket Yosher (Hilchos Taanis 12, p.114) writes, "Once I asked my rebbe, the Terumas HaDeshen, to permit me to eat during the days of selichos, so I would have the strength to learn as I do all days of the year. He replied that the scholars of the past also knew that fasting would make people weak and that it would be hard for them to learn. Nevertheless, they instituted the custom of fasting during selichos. Therefore, I can't permit you to eat."
Rebbe Dovid of Lelov zt'l once traveled by foot because he couldn't afford to hire a wagon. Someone stopped his horse and buggy beside Rebbe Dovid and offered him a ride.
When they arrived at their destination, Rebbe Dovid thanked him and said, “I have a beis medresh in Lelov. Come there on the first night of selichos.”
The man thought, “I did him a favor, and now he wants to take advantage of me and use me for his minyan for selichos. One thing is certain: I am not going to his beis medresh for selichos.”
On the first night of selichos, Rebbe Dovid entered his beis medresh and looked around. The person who gave him the ride wasn’t there yet, so he returned to his room.
A few times, he entered the beis medresh, looked around, and when he didn't see the person who drove him, he returned to his study.
At this time, the one who gave him a ride was in his home, in a village near Lelov. He thought, “Rebbe Dovid is a holy man, after all. He asked me to come to his beis medresh for selichos. Why shouldn’t I go?”
He drove to the Lelover Rebbe’s beis medresh. When the Rebbe came out this time, he saw him and immediately began the selichos.
After selichos, he told him, “You did me a favor this year, and I wanted to give you a brachah. I asked you to come on the first day of selichos since it is a great eis ratzon in heaven for the brachos to take effect. I give you a brachah that you and your descendants should enjoy immense wealth and long lives."
This account was relayed to me by the great-grandson of the recipient of this brachah. He attested, "I am a direct descendant of this individual, and I can testify that the blessing has been fulfilled. Throughout the subsequent generations, our family has experienced prosperity, and everyone has enjoyed long lives."
The Tur (581) writes, "Most people fast on the first day of selichos."
