Rabbi Yishmael was a great Torah sage, a colleague of Rabbi Akiva

Once, he was not careful enough about reading by lamplight on Shabbos, and he ended up tilting the lamp [considered a form of kindling, it causes oil to flow to the wick].

What did he do next? He wrote it down: “I, Yishmael ben Elisha, read by lamplight and tilted the lamp on Shabbos.” And he said that when the Temple would be rebuilt, he would bring a fine sin offering. (Shabbos 12b)

That teaches something important. Past sins do not mean a person is rejected. But they also do not just disappear because time passed. A person should expect that real repair may still be needed.

That is not meant to create shame. It is meant to create honesty. Teshuvah (repentance) means facing the truth, taking responsibility, and repairing what can be repaired.

In another version of this incident, he caught himself just in time from tilting it and declared “How great are the words of the sages”, b/c the sages had decreed one shouldn’t read by lamp light on Shabbos as it may lead to tilting the lamp, causing oil to flow to the wick”