question #1 Sahih al-Bukhari 2604, Book 51, Hadith 38 : What is the significance of offering two rak`at upon returning from a journey in Islamic tradition?

I sold a camel to the Prophet (ﷺ) on one of the journeys. When we reached Medina, he ordered me to go
to the Mosque and offer two rak`at. Then he weighed for me (the price of the camel in gold) and gave
an extra amount over it. A part of it remained with me till it was taken by the army of Sham on the day
of Harra.”