'Message' in the Bible

They say “To whom would He teach knowledge?And to whom would He explain the message?Those just weaned from milk?Those just taken from the breast?

“As often as it passes through, it will seize you;For morning after morning it will pass through, by day and by night,And it will be sheer terror to understand what it means.”

Who has believed [confidently trusted in, relied on, and adhered to] our message [of salvation]?And to whom [if not us] has the arm and infinite power of the Lord been revealed?