4 This passive participle or adjective is normally used to describe cities or walls as “fortified” or “inaccessible.” All the lexicons, however, agree in seeing it used here metaphorically of “secret” or “mysterious” things, things that Jeremiah could not know apart from the Lord’s revelation. G. L. Keown, P. J. Scalise, and T. G. Smothers (Jeremiah 26–52 [], ) make the interesting observation that the word is used here in a context in which the fortifications of Jerusalem are about to fall to the Babylonians; the fortified things in God’s secret counsel fall through answer to prayer.

In other versions

Call to me and I will answer you, and will tell you great and hidden things that you have not known.

‘Call to me and I will answer you and tell you great and unsearchable things you do not know.’

Call to me and I will answer you and tell you great and incomprehensible things you do not know.

Ask me and I will tell you remarkable secrets you do not know about things to come.

‘Call to me, and I will answer you, and I will tell you great things and inaccessible things that you have not known.’

Call unto me, and I will answer thee, and shew thee great and mighty things, which thou knowest not.

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