We find the soul repeatedly described as the “breath” of God.
Indeed, one Hebrew word for soul, neshamah, comes from the same root as neshimah (“breath”).
In its account of the creation of man the Torah tells of how God “breathed in his nostrils a breath of life (nishmat chayyim).”
A similar expression is found in the daily morning prayers, in which we say, “and You have breathed it [my soul] into me.”
As the Zohar points out, neflchah (“breathing into”), used in both these citations, implies a most forceful expulsion of air, in which a person expends his innermost reserves of life-sustaining breath.
—Rabbi Adin Steinsaltz