They say it daily, morning and evening. This prayer is called the Shema, which is the first word of the verse.
وَتُدْعَى هٰذِهِ ٱلصَّلَاةُ « شِمَاعَ » ،‏ وَهِيَ ٱلْكَلِمَةُ ٱلْأُولَى فِي ٱلْآيَةِ بِٱللُّغَةِ ٱلْعِبْرَانِيَّةِ .‏