He knew classical, semitic and modern languages, among French, Italian and German.
He was the senior librarian of king Felipe V of Spain, and a member of the Secretary of State.
[1] He was a native of Seville, a descendant of the House of Alba, one of the most illustrious families of the Spanish, and Portugues nobility.
[1] He was a founder Member of the Royal Spanish Academy in 1713, Secretary of the King of Spain and a Knight of the Military Order of Alcantara.
[2] Some of Don Gabriel's poetic works were printed in 1744 by Diego de Torres Villarroel, Professor of Mathematics and astronomer at the Salamanca University, in Diego de Torres Villarroel, under the title La Burromaquia, (something like "Treatise on the things related to Donkeys"), accompanied by some 17th-century mystical style religious poems.