For those who asked what this is (Saudi national flag) and what it says (from Wiki):

The Arabic inscription on the flag, written in the Thuluth script, is the shahada or Islamic declaration of faith:

لَا إِلٰهَ إِلَّا الله ومُحَمَّدٌ رَسُولُ الله
lā ʾilāha ʾillā l-Lāh wa Muḥammadun rasūlu l-Lāh
"There is no god but God and Muhammad is the messenger of God"