That's true in the
   [1]https://en.wikipedia.org/wiki/Cataphatic_theology
   but not true in the
   [2]https://en.wikipedia.org/wiki/Apophatic_theology
   or negative theology (describing God only by what God is not).

   It's likely that Hume was unaware of apophatic theology as it's
   not part of the Catholic -> Protestant -> Rationalist -> Atheist
   tradition but rather part of the Eastern Orthodox Christian
   (middle eastern, not far eastern, although they had forays there
   too) theology.

References

   Visible links
   1. https://en.wikipedia.org/wiki/Cataphatic_theology
   2. https://en.wikipedia.org/wiki/Apophatic_theology