Now it may well be asked, why our Lord ordered His action to be concealed, and yet it could not be kept hid for an hour? But it is to be observed, that the reason why, in doing a miracle, He ordered it to be kept secret, and yet for all that it was noised abroad, was, that His elect, following the example of His teaching, should wish indeed that in the great things which they do, they should remain concealed, but should nevertheless unwillingly be brought to light for the good of others. Not then that He wished any thing to be done, which He was not able to bring about, but, by the authority of His teaching, He gave an example of what His members ought to wish for, and of what should happen to them even against their will.
Reproduced in full. Translation: Oxford 1841 (Newman), public domain (Public domain).
Also cites: see Greg., Moral., 19, 22