There are people who think that God calls us by our capacity. Many believe that the apostle Paul was great for the studies he developed with Gamalier, but that is false, since he himself said: “But I certify you, brethren, that the gospel which was preached of me is not after man. For I neither received it of man, neither was I taught it, but by the revelation of Jesus Christ.” ( Galatians 1:11-12).
God does not call us because of our ability, because we are intellectual or illiterate, because we are rich or poor, because we are small or tall, before the Father of lights this does not have any kind of meaning, God does with whomever He wants and trains him as you can not imagine, and we can see this with a character named Peter, who, being a man without studies, preached a message and thousands converted to Christ.
In the Bible we have another very interesting story, and it is about Moses, considered the greatest leader of the old testament. In chapter four of the book of exodus, God calls him, shows him signs to see how powerful God is, and appointed him as the deliverer of the people of Israel from Egypt.