“Truly the signs of an apostle were accomplished among you with all perseverance, in signs and wonders and mighty deeds” (2 Corinthians 12:12).
Much like the apostles who accompanied Jesus during His earthly ministry, the Apostle Paul verified his calling through the miraculous works God performed through him. Some of those works included the act of laying his hands upon the sick and their subsequent recovery (Acts 28:8, compare with Luke 9:1-6) and raising the dead (Acts 20:7-12 compare with Matthew 10:1-8). It was highly unlikely that the false apostles in Corinth could point to similar validations.
While these false teachers may have claimed to possess a similar degree of apostolic authority, Paul supplied the Corinthian church with hard evidence:“…an exhaustive demonstration of the power God gives to a genuine messenger of his in the miracles, signs and works of spiritual power that you saw with your own eyes” (Phillips).
One source provides us with a definition of the “signs and wonders and powerful deeds” (NET) referenced within this passage…
“The words signs and wonders and mighty deeds do not describe three different types of miracles, but rather miracles viewed in three different aspects. Signs were miracles that conveyed a definite meaning to human intelligence. Wonders, on the other hand, were so remarkable that they stirred up human emotions. Mighty deeds were performances that were obviously of superhuman power.” (1)
Yet even though God worked unusual miracles through Paul the Apostle (see Acts 19:11-12), he did not employ them as promotional tools. Nor were they designed to provide a spectacle for the entertainment of an audience. Instead, these “signs and wonders and mighty deeds” served to authenticate Paul’s apostolic authority and confirm the message of salvation through Christ he proclaimed.
So just as a signpost identifies (or points the way to) a destination, these miraculous signs were not the object of Paul’s work. However, they helped lay the groundwork for another of Paul’s objectives for the Corinthian church: spiritual growth and maturity (2 Corinthians 7:1). Thus, a person who found healing and salvation as a result of God’s ministry through Paul would reap the benefit in this world and the world to come.
Finally, we should remember that Jesus expressed His displeasure with those who refused to accept Him in the absence of such miraculous works when He said, “Unless you people see signs and wonders, you will by no means believe” (John 4:48). Because of this, we can say that these signs, wonders, and miraculous works did not represent the foundation of Paul’s ministry but served as a validating component of his ministry.
(1) William Macdonald, Believer’s Bible Commentary Edited by Arthur Farstad Thomas Nelson Publishers (2 Corinthians 12:12)