Kun

Kun (كن) is an Arabic word for the act of manifesting, existing or being. "Kun fayakūn" has its reference in the Quran cited as a symbol or sign of God's mystical creative power.

In The Quran

(2:117) Initiator of the Universes and the Earth, when He decrees a command, He merely says to it, "Be" (Arab. كُنْ, kun), and it is (Arab. فَيَكُونُ, fayakūnu).