"He is the first; he is the last; he is the open; he is the hidden; and he has knowledge of everything.’ – Surah Hadīd (57), Verse 3
In the khutba of the book Madaarijun-Nubuwwah, Shaikh Abdul-Haqq Muhaddith Dehlwi states that this verse is both the praise of Allah and the praise of His Beloved ﷺ.The Holy Prophet ﷺ is the first of all, the last of all, heﷺ is evident to all, heﷺ is obscured, and heﷺ has knowledge of everything.
The Holy Prophetﷺ is the first of all – Before the world, Hereafter and everything else, the first thing created was the Noor of Rasoolullah ﷺ,
In the case of his physical body, Sayyiduna Adamعليه سلام is the father of Rasoolullahﷺ, but in reality Rasoolullahﷺ is the source of Sayyiduna Adamعليه سلام. A tree bears flowers even though the tree itself is from a flower. The flower of this orchard of creation is Rasoolullahﷺ. Prophethood was first bestowed to him, as he himself states,
"I was already a prophet when Adamعليه سلام was between sand and water (i.e. in the process of being created)"
On the Day of Covenant, when it was asked by Allah ,
“Am I not your Lord?”,
The Holy Prophetﷺ was the first to reply,
“Indeed You are.” – Surah A’rāf (7), Verse 172.
On the Day of Qiyaamat, Rasoolullah’sﷺ grave will be opened first. He’ll be commanded first to both make sajda and intercede (Shafa'ath). Bear in mind that the door of intercession will only be opened by the Holy Prophetﷺ. He’ll also be the first to open the doors of Jannah and enter it. All the other Prophets(Alaihimussalam) will enter after him. It will be Rasoolullah’sﷺ Ummah to first enter Jannah, and the other nations will follow us into Paradise. In short, the crown of being the first and having precedence is set on his blessed head. The first day (i.e. Jumua, Friday) was bestowed to the Holy Prophetﷺ. Yet in spite of all these things, the Holy Messengerﷺ is also last.
Ref:
{ Shan e Habiburahman - The beloved Majesty } by Mufti Ahmed Yaar Khan.