For the accustomed security of the Quraysh -
1- i.e., the honor and reputation AllŒh had given them as guardians of the Holy KaÔbah, which allowed them to travel without fear of being harmed.
إِۦلَٰفِهِمۡ رِحۡلَةَ ٱلشِّتَآءِ وَٱلصَّيۡفِ
Their accustomed security [in] the caravan of winter and summer -
1- i.e., the trading caravans that traveled south in winter and north in summer.
فَلۡيَعۡبُدُواْ رَبَّ هَٰذَا ٱلۡبَيۡتِ
Let them worship the Lord of this House,
1- i.e., the KaÔbah.
ٱلَّذِيٓ أَطۡعَمَهُم مِّن جُوعٖ وَءَامَنَهُم مِّنۡ خَوۡفِۭ
Who has fed them, [saving them] from hunger and made them safe, [saving them] from fear.