Jeremiah 7:27

Therefore thou shalt speak all these words unto them
Before mentioned in the chapter; exhortations to duty, dehortations from sin, promises and threatenings: but they will not hearken to thee:
so as to reform from their evil ways, and do the will of God; they will neither be allured by promises, nor awed by menaces: thou shalt also call unto them;
with a loud voice, showing great vehemency and earnestness, being concerned for their good, and knowing the danger they were in: but they will not answer thee;
this the Lord knew, being God omniscient; and therefore, when it came to pass, it would be a confirmation to the prophet of his mission; and being told of it beforehand, was prepared to meet with and expect such a reception from them; so that he would not be discouraged at it; and at the same time it would confirm the character given of this people before.