Jeremiah was a young boy who is called by God for the specific mission of God. When he heard the call of God, he was ambiguous to accept the call of God “Ah, Lord God! Behold, I do not know how to speak, for I am only a youth” (Jer 1: 6). For David Stanely,
Reaction to the divine call is common in the call narratives. Jeremiah’s reaction comes as a response to the divine call to be a prophet ‘to the nations.’ The young prophet thoroughly understands the nuance of the divine call and hence hesitates. The reaction is twofold:” I do not know how to speak and I am a youth.” Jeramiah is called to be a prophet hence he feels the burden of delivering the Word to the people. He hesitates as he has no prior training. He also identifies himself as a youth or boy. Since Jeremiah was aware of his limitations and hence he is reluctant to give a positive response to the divine call. Knowing one’s limitations is the first stage of realization. It is true that Jeremiah knows himself well but it is God who knows him better.
Further, he says about the reaction of Jeremiah, it was God who called Him and made Him to be the messenger for His people. Even though he was finding difficult to give positive response but God made him worthy to be His own.
 M. David Stanly Kumar, “Prophetic Spiritualty of Vocation and Mission in Jeramiah 1: 4-10,” Indian Theological Studies Vol, 51. no. 2 (2014), 150.