Maaseh Rav Siman 49
Can copy this into an AI, or connect the whole library to your assistant. For deeper learning, you can directly use the original seforim, sites, and apps.
תחנון לא יאמר פסוק ויאמר דוד שנאמר גבי פורעניות רק יתחיל רחום וחנון:
Sefaria Community Translation
In Tachanun one should not say the verse 'V'Yomer Dovid' as it is said regarding retribution, rather one should begin the prayer with 'Rachum V'Chanun'.