A newspaper reporter does not always reveal their source of information. It is a matter of confidentiality and integrity and some journalists have gone to jail standing on those convictions. The source is of high importance; if the tip comes from someone of character; his or her word carries more weight.
Thus saith the LORD. When prophets used the previous phrase, His chosen people paid attention. God’s character is beyond question; He does not lie. “Thus saith the LORD the King of Israel, and his redeemer the LORD of hosts; I am the first, and I am the last; and beside me there is no God (Isaiah 44:6 KJV).”