Helmut Thielicke said this quote
“ It is a mistake for anyone who is just in this stage to appear before a church as a teacher. He has outgrown the naivete with which in young people’s work he might by all means have taken this part. He has not yet come to that maturity which would permit him to absorb into his own life and reproduce out of the freshness of his own personal faith the things which he imagines intellectually and which are accessible to him through reflection. We must have patience here and be able to wait. For the reasons I have mentioned I do not tolerate sermons by first-semester young theological students swaddled in their gowns. One ought to be able to keep still. During the period when the voice is changing we do not sing, and during this formative period in the life of the theological student he does not preach. ”