Paul’s letters can be difficult and demanding, as other Christians also noticed (compare 2 Peter 3:16).
his physical presence is unimpressive: Paul did not have an overpowering presence that forced people to obey (compare 2 Corinthians 1:24; 1 Corinthians 2:1–5). The earliest descriptions of Paul’s appearance (Acts of Paul and Thecla, around AD 200) describe him as "a man of small height, almost bald, with crooked legs, but with a good body and eyebrows meeting. His nose was hooked, full of grace, for sometimes he appeared like a man and sometimes had the face of an angel."
his speaking is of no account: Unlike Apollos (Acts 18:24), Paul was not a skilled speaker or captivating orator when he came to Corinth (see 2 Corinthians 11:6; 1 Corinthians 2:3–4). However, his message was filled with a power beyond human speech, as it was given in the Holy Spirit.