In the book «Elementos de Retórica» by the 18th-century Spanish priest and latinist Calixto Hornero, there is the following sentence (link to 1815 edition):
Cernere est plurimos, qui sibi parum sapiant. Quotus enim quisque est qui Jesum Christum, pro eo ac debet, ipsa plus anima diligat, virtuti posthabitis inanibus hominum perditorum oblectamentis? Multum hac in re ab hominibus vulgò peccatur.
The Spanish translation given, rendered in English would be:
It is an easy thing to see a great many [people] who are not very sane for theirselves. For how many but a few are there who love Jesus Christ as they must, more even than their own life, esteeming virtue higher than the frivolous pleasures of the world? A great fault is commonly commited among men in this [aspect].
I have four questions:
(1) Why is the 'easily' ('facilè') ommited in 'Cernere est plurimos'?
(2) What does 'pro eo ac debet' exactly mean?
(3) In 'ipsa plus anima', are 'ipsa' and 'anima' comparative ablatives? In this 1820 edition the circumflex accent isn't used for long-short vowel distinctions.
(4) How does 'virtuti posthabitis inanibus hominum perditorum oblectamentis' translate into 'esteeming virtue higher than the frivolous pleasures, etc. '? Isn't there some missing verb and adverb combination meaning 'esteeming higher'? Instead, we only have a dative ('virtuti') before an ablative phrase.
So, to sum up, I am asking for both an answer to these questions and a better translation.