Isaiah 28:10

For precept must be upon precept -This is probably designed to ridicule the concise and sententious manner of the prophets, and especially the fact that they dwelt much upon the same elementary truths of religion. In teaching children we are obliged to do it by often repeating the same simple lesson. So the profane and scoffing teachers of the people said it had been with the prophets of God. It had been precept upon precept, and line upon line, in the same way as children had been instructed.