Refuting some of the common points of opposition to the use of casting lots:
1. The unbelievers casted lots at the cross to get the clothes of Jesus:
They did this because it was fulfillment of God-ordained prophecy, as mentioned by the prophet in Psalm 22:18:
Matthew 27:35KJV
35And they crucified him, and parted his garments, casting lots: that it might be fulfilled which was spoken by the prophet, They parted my garments among them, and upon my vesture did they cast lots.
Lev. 16:8 KJV
8And Aaron shall cast lots upon the two goats; one lot for the LORD, and the other lot for the scapegoat.
2. They 11 apostles were instructed to wait so they should not have casted lots to pick Matthias:
The 11 apostles were instructed to wait for power from the Holy Spirit when they were baptized with the Holy Spirit, but they were not without the Holy Spirit:
Acts 1:4-5 KJV
4And, being assembled together with
them, commanded them that they should not depart from Jerusalem, but wait for the promise of the Father, which,
saith he, ye have heard of me.
5For John truly baptized with water; but ye shall be baptized with the Holy Ghost not many days hence.
Acts 1:8 KJV
8But ye shall receive power, after that the Holy Ghost is come upon you...
3. The 11 apostles did not have the Holy Spirit yet so that's why they casted lots because they didn't know how to determine God's will:
Jesus gave the Holy Spirit to His 11 apostles post-resurrection, pre-ascension, so they already had the Holy Spirit. That means it's possible to still have the Holy Spirit and see casting lots as a valid method of determining God's will:
John 20:22 KJV
22And when he had said this, he breathed on
them, and saith unto them, Receive ye the Holy Ghost...
4. Paul is the real 12th apostle:
There isn't anything in scripture that I am aware of that creates a problem with having 13 or more apostles. The 11 apostles in Acts 1:24-26 believed Matthias was an apostle of God through the casting of lots. They also accepted Paul as an apostle of God. If the apostles all accepted each other as valid maybe we should too?
Acts 1:26 KJV
26And they gave forth their lots; and the lot fell upon
Matthias; and he was numbered with the eleven apostles.
2 Timothy 1:1 KJV
1Paul, an apostle of Jesus Christ by the will of God, according to the promise of life which is in Christ Jesus,
5. There can't be 13 apostles:
This claim is not found in scripture as far as I am aware.
6. Casting lots is not recommended for Christians:
And yet the Bible says that Christians, who were filled with the Holy Spirit, were using the method of casting lots to determine God's will:
John 20:22 KJV
22And when he had said this, he breathed on
them, and saith unto them, Receive ye the Holy Ghost...
Acts 1:26 KJV
26And they gave forth their lots; and the lot fell upon
Matthias; and he was numbered with the eleven apostles.
Conclusion: Having weighed and divided the scripture, I have come to the conclusion that casting lots is a method that can be used to determine God's will, supplemented by prayer. Furthermore, the New Testament does not forbid casting lots.