To how many disciples did the risen Jesus appear?

1 Corinthians 15 contains early testimony to Jesus’ resurrection appearances, with Paul listing the individuals and groups whom Jesus appeared. However, Paul makes a mistake concerning how many disciples Jesus had at this point.

Paul includes in his list Jesus’ disciples, “the twelve”:

For I handed on to you as of first importance what I in turn had received: that Christ died for our sins in accordance with the scriptures, and that he was buried, and that he was raised on the third day in accordance with the scriptures, and that he appeared to Cephas, then to the twelve. Then he appeared to more than five hundred brothers and sisters at one time, most of whom are still alive, though some have died. Then he appeared to James, then to all the apostles. Last of all, as to someone untimely born, he appeared also to me. [1 Corinthians 15:3-8 (NRSV)]

The problem with this is that Jesus didn’t have twelve disciples at the time of his resurrection appearances; due to Judas Iscariot’s betrayal he only had eleven.

Acts 1:3-9 describes how the resurrected Jesus spent forty days with his disciples. At the end of this period, Jesus is taken up to heaven, and the disciples return to Jerusalem. At this point we are given a list of their names:

Then they returned to Jerusalem from the mount called Olivet, which is near Jerusalem, a sabbath day’s journey away. When they had entered the city, they went to the room upstairs where they were staying, Peter [1] and John [2], and James [3], and Andrew [4], Philip [5] and Thomas [6], Bartholomew [7] and Matthew [8], James son of Alphaeus [9], and Simon the Zealot [10], and Judas son of James [11]. [Acts 1:12-13 (NRSV)]

There are eleven disciples listed here (note that Judas son of James is not the Judas Iscariot that betrayed Jesus), and Jesus has finished appearing to his disciples and ascended to heaven.

Only then is a replacement for Judas Iscariot appointed, taking the number of Jesus’ disciples back up to twelve:

In those days Peter stood up among the believers (together the crowd numbered about one hundred and twenty people) and said, … ‘For it is written in the book of Psalms, “Let his homestead become desolate, and let there be no one to live in it”; and “Let another take his position of overseer.” So one of the men who have accompanied us throughout the time that the Lord Jesus went in and out among us, beginning from the baptism of John until the day when he was taken up from us–one of these must become a witness with us to his resurrection.’ So they proposed two, Joseph called Barsabbas, who was also known as Justus, and Matthias. Then they prayed and said, ‘Lord, you know everyone’s heart. Show us which one of these two you have chosen to take the place in this ministry and apostleship from which Judas turned aside to go to his own place.’ And they cast lots for them, and the lot fell on Matthias; and he was added to the eleven apostles. [Acts 1:15,20-26 (NRSV)]

So did Jesus appear to 12 disciples as is claimed by Paul, or to 11 as is claimed by Acts?