Jeremiah suggested two difficulties, the first inexperience, the second timidity. God now removes the first of these. Inexperience is no obstacle where the duty is simple obedience His timidity is removed by the promise given him in the next verse.
Related Commentaries of Jeremiah 1:7
Jeremiah 1:7
7 But the LORD said unto me, Say not, I am a child: for thou shalt go to all that I shall send thee, and whatsoever I command thee thou shalt speak.