Farther, if the word declared have reference to the past, it must be considered that He, being made man, declared the doctrine of the Trinity in unity, and how, and by what acts we should prepare ourselves for the contemplation of it. If it have reference to the future, then it means that He will declare Him, when He shall introduce His elect to the vision of His brightness.
Reproduced in full. Translation: Oxford 1841 (Newman), public domain (Public domain).
Also cites: in loc.