Question:
Why is it prohibited to confess and say Viduy on Rosh Hashanna?
Answer:
Hello,
The reason is that on Rosh Hashana we stand in judgment before Hashem, and the mere mention of sin, especially sins committed, can have a detrimental effect. Not that Hashem "forgets"; however, mentioning sin brings the topic up. Therefore, we don't say viduy on Rosh Hashana.
Best wishes
