In Isaiah 52:14, this signifies the Lord's appearance in humility. (The Inner Meaning of the Prophets and Psalms 52)

In Lamentations 4:8, this signifies the obscurity of divine truth to such a point that it was no longer visible. (Apocalypse Explained 196[3])

In Daniel 3:19, this signifies the antagonism of people represented by ‘Babylon' against the goods and truths of the Lord's church. (The Inner Meaning of the Prophets and Psalms 174)

As with many common verbs, the meaning of “to say” in the Bible is highly dependent on context. Who is speaking? Who is hearing? What is it about? Is it a command, a message, an apology, instruction? All these things enter into the meaning of “say.” In general, though, “saying” has to do with sharing truth at various levels -- from the most exalted power people can have to perceive the Lord's desires directly to the most basic of orders issued to people at their lowest.