It was in God's plan that Matthias be chosen as the replacement disciple. Do NOT forget God also had a plan for Barsabbas. We KNOW Barsabbas was a Believer and therefore God had a plan for him. God has a plan for even the Unbelievers--check out Pharaoh. Just because he was not chosen as one of the twelve does not mean God did not use him for His good purpose. He was a member of the original body of Believers. There at the beginning -helping to spread the word which has continued to spread until today. He was there before the Word was written---it all had to be spread person to person and he helped spread the message. Without one single doubt, God used him and used him well.
When I first read this passage, I felt sorry for Barsabbas--not being chosen. I was gently reminded---it is God's plan that he was not chosen---He still used him for his good glory---because of who I know God to be--this was all part of the plan. God does not make mistakes and all works for good for those that are called according to HIS purpose.
I was not chosen to live out my life in a marriage---I am in a large company of women who were chosen to live alone. God has a good purpose and can use each of us well in this state of singleness. The bottom line is---I was chosen--chosen to be alone---just as Barsabbas was chosen to not be in the twelve. It is a step of backing up and choosing to view life through a different lens. This view shows I was chosen to be alone---not I was not chosen to remain in a marriage. God's perfect plan for each of us---ALL for HIS GOOD PURPOSE.
"Judas must now be replaced. The replacement must come from the company of men who stayed together with us from the time Jesus was baptized by John up to the day of his ascension." vs 21-22
" ' You, O God, know every one of us inside and out. Make plain which of these two men you choose to take the place in this ministry and leadership that Judas threw away in order to go his own way.' They then drew straws. Matthias won and was counted in with the eleven apostles." vs 24-26