Speak
Like "say," the word "speak" refers to thoughts and feelings moving from our more internal spiritual levels to our more external ones -- and ultimately from the Lord, who is in a sense the most internal spiritual level of all. This is generally called "influx" and "perception" in the Writings, meaning they are thoughts and feelings that flow in in a complete way from the Lord, rather than being things we have to think about and figure out. On a number of occasions "speak" and "say" are used together; in these cases "speak" refers more to intellectual instruction in matters of thought and "say" refers more to feelings and affections that flow in directly.
Isaiah 10:3-5
3
What will you do in the day of visitation, and in the desolation which will come from afar? To whom will you flee for help? Where will you leave your wealth?
4
They will only bow down under the prisoners, and will fall under the slain. For all this his anger is not turned away, but his hand is stretched out still.
5
Alas Assyrian, the rod of my anger, the staff in whose hand is my indignation!
