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.
Jeremiah 6:15-16
15
Were they ashamed when they had committed abomination? No, they were not at all ashamed, neither could they blush. Therefore they shall fall among those who fall; at the time that I visit them, they shall be cast down," says Yahweh.
16
Thus says Yahweh, "Stand in the ways and see, and ask for the old paths, 'Where is the good way?' and walk in it, and you will find rest for your souls. But they said, 'We will not walk in it.'
