'Speech' in the Bible

Then Moses said to the Lord, “Please, Lord, I am not a man of words (eloquent, fluent), neither before nor since You have spoken to Your servant; for I am slow of speech and tongue.”

But Moses said to the Lord, “Look, [my own people] the Israelites have not listened to me; so how then will Pharaoh listen to me, for I am unskilled and inept in speech?”

But Moses said before the Lord, “Look, I am unskilled and inept in speech; how then will Pharaoh listen to me and pay attention to what I say?”

Now concerning everything which I have said to you, be on your guard; do not mention the name of other gods [either in a blessing or in a curse]; do not let such speech be heard [coming] from your mouth.