Note 3 at 1Co 2:3: Paul was describing a self that seemed completely inconsistent with the impression that his actions gave and that he promoted in his own teaching. However, there is no contradiction. He was simply describing how he felt in his flesh (see note 3 at Ro 7:18).

He had negative feelings and emotions, but he didn't let them dominate him. Instead, he walked in the reality of who he was in the Spirit. The end result was that in his actions, he was not weak, fearful, or trembling. However, this wasn't because he didn't feel those things. He had learned not to live according to his own feelings but to let Christ live through him (Ga 2:20).

The reason Paul described his natural feelings was to remind the Corinthians that he didn't rely on himself when he ministered to them. If he had, they would not have seen the supernatural confirmation of the power of God that he described in 1Co 2:4. Therefore, they shouldn't reject his instruction, because it wasn't him that was speaking, but God speaking through him.