Words describe the two states in the development of emotions—ibbur (pregnancy) and leidah (birth).
Ibbur is the stage of concealment and internal development.
Leidah is revelation and outward manifestation.
When people whose souls are in a state of birth—with a concurrent unveiling of their cerebral and emotional powers—experience an intellectual arousal, a wave of activity is automatically unleashed in their heart, as well.
—Rabbi Adin Steinsalz