'Secret' in the Bible

For I do not wish you to be ignorant, brethren, of this secret -- that ye may not be wise in your own conceits -- that hardness in part to Israel hath happened till the fulness of the nations may come in;

And to Him who is able to establish you, according to my good news, and the preaching of Jesus Christ, according to the revelation of the secret, in the times of the ages having been kept silent,