Moses was a rotten speaker (speech impediment? slow thinker? hesitant speaker? garbled words?), but was expected to be a great leader.
Peter was the rock he would build his church on-- and he flat-out denied even knowing Christ during the Passion, and cussed anyone who accused him of being a follower.
David was a shepherd and became one of the greatest leaders of the Israelites.
Joseph was sold as a slave and ended up saving multiple countries from starvation.
Mary was a poor girl (12? 13? 14?) living in an obscure corner of the empire when the Annunciation happened.
Matthew was a tax collector (to be read: traitor to his countrymen and probably a thief) and was hand-picked to be one of Jesus’ Twelve Apostles.
Paul persecuted Christians all over the place, but ended up being one of the greatest theologians working on behalf of Christianity.
Joan of Arc was a peasant who helped bring the Hundred Years’ War to a close.
Bernadette Soubirous was a peasant— and six million people a year visit her grotto, where all sorts of people experience miracles, both physical and spiritual.
Faustina Kowalska applied for a convent, and was written off as “nothing special”… but her Diary is the basis for one of the greatest devotions of the 20th century.
Therese of Lisieux died at age 24 after a long fight with tuberculosis— but still managed to become one of the greatest saints of modern times, according to Pope St. Pius X.
The Cure d’Ars and Solanus Casey were both so ignorant, and such rotten academics, they almost didn’t get ordained in the first place— and yet they converted so many hearts (and performed a few miracles along the way).
That was thirteen off the top of my head. History is full of God using the smallest and the weakest and the most ignorant to do his work. Half the point is that they
are small and weak and poor and ignorant— there’s no way that an illiterate person with hardly any education can become a Doctor of the Church otherwise.
St. Vincent de Paul said–
“It is on humble souls that God pours down His fullest light and grace. He teaches them what scholars cannot learn, and mysteries that the wisest cannot solve He can make plain to them.”