Peter cast lots and it fell to Mathias, but the Lord personally selected Saul, who became Paul and we know it was Paul who probably had one of the greatest influences in the growing Apostolic Church. Mathias, we never hear from again. That’s why it’s so important to go to the Lord with all things and not make assumptions. We don’t tell the Lord, “Hey Father….here’s a couple of choices for apostle replacement we like, pick one and we’ll say you chose him”, rather than asking Him, “Father, who would you have us replace Judas with to teach your word? Your will be done, not ours”. Jesus personally calls upon Paul and the Holy Spirit teaches Paul everything he needed to know to equip him for his mission. 🙂