Full Idea
The modern emphasis has been on the connection between essential properties and the properties that an object must have essentially. But traditionally there is also the connection between essential properties and the sort of thing that it is.
Gist of Idea
Modern emphasis is on properties had essentially; traditional emphasis is on sort-defining properties
Source
Baruch Brody (Identity and Essence [1980], 5.6)
Book Reference
Brody,Baruch: 'Identity and Essence' [Princeton 1980], p.131
A Reaction
These are the modal essence and the definitional essence. My view is that he has missed out a crucial third (Aristotelian) view, which is that essences are explanatory. This third view can subsume the other two.