Ibrahim AS was one of the prophets sent to the Arabs. He established religious practices that lasted for thousands of years, until the coming of the Prophet ﷺ. The first was treating Makkah as sacred (al-Haram). Inside its boundaries, things that are normally allowed, such as hunting animals or even plucking a leaf, became forbidden. The second was honouring the Ka'bah.
The third was the four Sacred Months: Dhu al-Qa'dah, Dhu al-Hijjah, Muharram and Rajab. During these months all hostility had to stop, and no one was allowed to fight. The fourth was the hajj with all of its rites. These included tawaf (walking around the Ka'bah), sa'i (walking between the hills of Safa and Marwah), sacrificing animals, and decorating the animals set aside for sacrifice.
Many non-Muslim researchers say that Islam took these practices from pagan culture. They overlook the fact that the practices go back to Ibrahim AS, who taught pure monotheism (tawhid). The Muslim view is that the Prophet ﷺ followed the original religion of Ibrahim AS. He cleansed it of the paganism that had crept in over the centuries between them.
These rites of Ibrahim AS are why the sanctity of Makkah, the Sacred Months and the hajj were already familiar to the Arabs before Islam. The Prophet ﷺ restored their original monotheistic meaning rather than inventing them. Makkah was also the site of the first House ever built for the worship of Allah. Ibrahim AS and Ismail AS built it there (Qur'an 3:96). Earlier messengers were each sent to a particular nation. Musa AS and Isa AS, for example, were sent to the Children of Israel. It was therefore fitting that the first call to all of mankind came from the city that held humanity's first house of worship.
O our Lord! Send amongst them a prophet of their own, who shall recite to them Your signs, and teach them the Book and wisdom, and purify them.
Ibrahim AS made this du'a while building the Ka'bah with Ismail AS, asking Allah to send a prophet from Ismail AS's descendants.
A person would see the murderer of his father doing tawaf, and he would not touch a hair on his head, because Makkah is sacred.
وَمَن دَخَلَهُ كَانَ آمِنًا
“Whoever enters it [i.e., the Haram] shall be safe.”
This ayah's declaration that "whoever enters it shall be safe" is part of the Qur'an's confirmation of the sanctuary status Ibrahim (AS) established for Makkah at this event.
أَوَّلَ بَيْتٍ وُضِعَ لِلنَّاسِ لَلَّذِي بِبَكَّةَ
“The first House [of worship] established for mankind was that at Makkah.”
Cited as the first House ever established for mankind, making Makkah the fitting origin of the first universal call.
“Our Lord, send from amongst them a messenger.”
Ibrahim (AS)'s prayer recorded in this event's post is the same dua preserved in this ayah (Q2:129), asking Allah to send a prophet "of their own" to his descendants.