The Gemara (Bava Kama 97:) states, "On the coin of Avraham Avinu, there was a וזקינה זקן, an old man and an old woman on one side, and a ובתולה בחור, a boy and girl on the other side. With this mintage, Avraham was teaching that even when one is elderly, it isn't too late. He can begin again, just like a young boy or girl.
Reb Issar Zalman Melzer zt'l once said to his student, Reb Nota Freund zt'l, "I turned eighty today. I must 'take myself into my hands' and begin learning!" He said this with total simplicity, as a young bachur in yeshiva might speak at the beginning of the zman. He realized that despite his age, it wasn't too late to turn over a new leaf.
We heard this story from one of the great talmidei chachamim of Yerushalayim shlita, who had an "open door" relationship with Reb Yosef Shalom Eliyashev zt'l.
Every year, on the night of Rosh Hashanah, he wanted to receive a brachah from Reb Eliyashev because this is the only time, during Aseres Yemei Teshuvah, that the brachah is טובה וחתימה כתיבה. After the first night, the brachah is טובה חתימה גמר, but we don't mention the כתיבה anymore.
However, despite his desire, he couldn't go to Reb Eliyashev. By the time he finished the davening and the tish he attended, it was late at night.
But one year in ט"תשע, when Reb Eliyashev was 99 years old, he decided that he would make the effort to receive a brachah. After the tish, at three o'clock in the morning, he went to Reb Eliyashev's home, knowing that Reb Eliyashev would have woken up by that time for the next day. (Reb Eliyashev would always awaken around that time to study Torah at night.) When he arrived, he heard Reb Eliyashev studying with sweetness.
Reb Eliyashev was startled when he saw him. The man explained, "It is nothing serious; it is just that I wanted to receive a brachah from the Rav for a טובה וחתימה כתיבה." He explained that although for Reb Eliyashev, it was already morning, a new day, for him, it was still nighttime, and therefore, Reb Eliyashev could give him the brachah for a טובה וחתימה כתיבה. Reb Eliyashev blessed him, and then Reb Eliyashev pointed to his Gemara and said, "We began the year with hischadshus!" He was saying that it was a new year, and he was putting in new effort and excitement in studying Torah.
The visitor was overwhelmed by what Reb Eliyashev said. Here is a ninety-nine-year-old gadol, already an expert in Torah, respected in Klal Yisrael as among the greatest gedolim and poskim. Yet he was beginning anew like a young bachur in yeshiva. On the other hand, you can find many young bachurim, or yungerleit, at the age of 25, and certainly when they reach 50 or 60, they feel that there is no hope for them to succeed in Torah. It isn't so. At any age, you can begin anew and grow in Torah.
The Mishnah (at the beginning of Zevachim) states, "All korbanos that are brought שלא לשמן (the person who brought it thought it was a different type of korban) the korban is kosher... The exception is the korban Pesach and a korban chatas (when one thinks it is another korban, the korban becomes pasul)."
Why are the korban Pesach and chatas different than all other korbanos?
Pesach was the first mitzvah that Bnei Yisrael received. The first must be performed in the best way, without any בדיעבד. Also, the korban chatas is brought by someone doing teshuvah, which means he is beginning his avodas Hashem brand new. And the beginning must be done with perfection.
