I have not spoken in secret, in a dark place of the earth: I said not unto the seed of Jacob, Seek ye me in vain: I the LORD speak righteousness, I declare things that are right.
I have not spoken in secret, in a dark place of the earth - not like the pagan oracles which gave their responses from dark caverns, with studied obscurity (Isaiah 48:16). Christ plainly quotes these words, thereby identifying Himself with Yahweh, John 18:20, "In secret have I said nothing."
I said not unto the seed of Jacob, Seek ye me in vain - When I commanded you to seek me (Yahweh did so, Isaiah 45:11, "Ask me," etc.), it was not in order that ye might be sent empty away (Deuteronomy 32:47). Especially in Israel's time of trial, God's interposition, in behalf of Zion hereafter, is expressly stated as about to be the answer to prayer (Isaiah 62:6-10; Psalms 102:13-17; Psalms 102:19-21). So in the case of all believers, the spiritual Israel.
I the Lord speak righteousness - what is veracious: not in the equivocal terms of pagan responses, fitly symbolized by the 'dark places' from which they were uttered.
I declare things that are right - true (note, Isaiah 41:26).