question #1 Sahih Muslim 1211f, Book 15, Hadith 124 : What is the significance of the new moon of Dhul-Hijja in the context of Hajj and Umra?

We set out with the Messenger of Allah (ﷺ) just at the appearance of the new moon of Dhul- Hijja. We had no other intention but that of performing the Hajj, whereupon the Messenger of Allah (ﷺ) said: He who among you intends to put on Ihram for `Umra should do so for `Umra. The rest of the hadith is the same.