The tourism of my nation is Jihad in the path of Allah, the Exalted
Authentic hadithعن أبي أمامة رضي الله عنه : أن رجلا، قال: يا رسول الله، ائذن لي في السياحة. فقال النبي صلى الله عليه وسلم : «إن سياحة أمتي الجهاد في سبيل الله عز وجل ».
Abu Umāmah (may Allah be pleased with him) reported: A man said: "O Messenger of Allah, allow me to travel." The Prophet (may Allah's peace and blessings be upon him) said: "The tourism of my Ummah is Jihad in the path of Allah, the Exalted."
Explanation
This Hadīth explains that acts of worship are restricted to matters that have textual evidence. A Muslim is only allowed to perform acts of worship in the way that the pure Shariah has dictated. The Messenger of Allah (may Allah’s peace and blessings be upon him) explained to the man who asked him to be allowed to travel for the sake of worship - which is a habit of the Christians – that the tourism of the Muslims is to spread Islam across the world and to perform Jihad in the path of Allah to elevate His religion.
Source · Narrated by Abu Daoud
From the Hadith Encyclopedia (hadeethenc.com).