Some people may only be reached through an invitation. That some believed after her testimony and many others believed after her invitation indicates that some people can be reached one way while others must be reached a different way. Paul used an intellectual approach to witness on Mars' hill. He even quoted their pagan poets. Paul used his knowledge of their beliefs to share the gospel in a way they understood.
Some people have a special ability to share the gospel through an intellectual appeal.
Some people may only be reached through intellectual appeals. Some who heard Paul on Mars' hill believed. The Bible also records how we can witness through relationships. Jesus spent three years with the disciples, but some still did not understand. During Pentecost they understood and became mighty witnesses.