Then said I, Ah, Lord God! behold I cannot speak; for I am a child. But the Lord said unto me, Say not, l am a child: for thou shalt go to all that I shall send thee, and whatsoever I command thee thou shalt speak. -Jeremiah 1:6-7
Jeremiah was young and felt a natural shrinking when sent upon a great errand by the Lord; but He who sent him would not have him say, “I am a child.” What he was in himself must not be mentioned but lost in the consideration that he was chosen to speak for God. He had not to think out and invent a message nor to choose an audience: he was to speak what God commanded and speak where God sent him, and this he would be enabled to do in strength not his own. Is it not so with some young preacher or teacher who may read these lines? God knows how young you are and how slender are your knowledge and experience; but if He chooses to send you, it is not for you to shrink from the heavenly call. God will magnify Himself in our feebleness. If you were as old as Methuselah, how much would your years help you? If you were as wise as Solomon, you might be equally as willful as he. Keep you to your message, and it will be your wisdom; follow your marching orders, and they will be your discretion.
[from Faith’s Checkbook by Charles H. Spurgeon]