In Genesis 11:1, in the phrase 'the whole earth was of one lip' means that people everywhere held to the same doctrine in its general aspects, 'lip' meaning doctrine, 'the earth' the Church. (Arcana Coelestia 1284)

In Isaiah 6:5, 7, this stands for our inner capacities and so for inward worship. (Arcana Coelestia 1286)

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.