I came across recently a quotation from Pope Benedict the XIII in a brief he addressed to the Dominicans in, I think, 1723, once again reassuring them on this point. The quotation illustrates the high regard the Church has for the doctrines of grace of St. Augustine and St. Thomas:
It is not surprising . . .that you should take amiss the malicious assertion which has been made, that Clement XI., in condemning the errors specified in his bull Unigenitus, designed in any sense whatever to attack the doctrine of St. Augustine and St. Thomas, or sought to diminish your reputation by subjecting the principal articles of your belief to the censures denounced in the said Constitution. I applaud your sensitiveness in this matter, and recognise you thereby as the true children of St. Thomas. In the whole of this affair your cause has never been separated from that of the Holy See; far from pitying you, I consider it highly to your honour to be identified with the Angelic Doctor, and to witness in your own persons that the agreement of his doctrine with the Divine oracles and the Apostolic decrees has not sufficed to restrain the unbridled license of these calumniators. It is strange that such insinuations should have been made, since the errors in question are distinctly condemned by the teaching of St. Thomas; and it has so happened, by a remarkable Providence, that his writings have been the means of overthrowing numberless forms of heresy which have arisen in the Church. I exhort you then to despise the slanders which it is attempted to propagate against your dogmas of grace efficacious by itself and of gratuitous predestination to glory without any prevision of merits, derived as they are from the works of St. Augustine and St. Thomas, from the word of God, from the decrees of Councils, and from the authority of the Fathers. We forbid, under canonical penalties, all persons whatsoever to give currency to such calumnies or spread such rumours. Continue to regulate yourselves by the teaching of our celebrated Doctor, which is more luminous than the day, and contains no alloy of error. Maintain and defend it with all vigour, inasmuch as it is the rule of Christian doctrine, and contains nothing but the pure verities of our holy religion. I announce this to you in order to dispel your fears, and to prove to you our deep interest in your welfare. This indeed is the least that we can do, having embraced your statutes, and made our profession of religion in your illustrious Order, from which Providence has now raised us to undertake the government of the Church. (From The Gallican Church: A History of the Church of France, Volume 2, by Rev. W. Henley Jervis [London: John Murray, Albemarle Street, 1872], 254-255)
For more, see here.
Published on the feast of St. Paul Miki and Companions.