Reformed Covenanter
Cancelled Commissioner
Since, however, we have frequently to mention the words essence and substance, we must determine the meaning of essence, lest in discussing facts we prove ignorant of the signification of our words. Essence is a reality which is, or the reality of those things from which it is, and which subsists inasmuch as it is permanent. Now we can speak of the essence, or nature, or genus, or substance of anything.
And the strict reason why the word essence is employed is because it is always. But this is identical with substance, because a thing which is, necessarily subsists in itself, and whatever thus subsists possesses unquestionably a permanent genus, nature or substance. When, therefore, we say that essence signifies nature, or genus, or substance, we mean the essence of that thing which permanently exists in the nature, genus, or substance.
For the reference, see Hilary of Poitiers on the definition of essence.
And the strict reason why the word essence is employed is because it is always. But this is identical with substance, because a thing which is, necessarily subsists in itself, and whatever thus subsists possesses unquestionably a permanent genus, nature or substance. When, therefore, we say that essence signifies nature, or genus, or substance, we mean the essence of that thing which permanently exists in the nature, genus, or substance.
For the reference, see Hilary of Poitiers on the definition of essence.