the writing of Matthew was by those who were saved and regenerated. That too must be taken into account.
Moreover, Mark 16 14-20 and Matthew 28:16-20 were said BY the resurrected Lord. Your point is not well-founded. The regeneration of them (the disciples) is shown in John chapter 20:21-22 and in the confession that is recorded.
21 Jesus said to them again, “Peace be with you. As
jthe Father has sent me,
keven so I am sending you.” 22 And when he had said this, he breathed on them and said to them
, “Receive the Holy Spirit. 23
If you forgive the sins of any, they are forgiven them; if you withhold forgiveness from any, it is withheld.”
Jesus came and stood among them and said,
“Peace be with you.”
27 Then he said to Thomas,
“Put your finger here, and see my hands; and put out your hand, and place it in my side. Do not disbelieve, but believe.”
28 Thomas answered him,
“My Lord and my God!”
The very last two verse states this truth:
30
Now Jesus did many other signs in the presence of the disciples, which are not written in this book;
31
but these are written so that you may believe that Jesus is the Christ, the Son of God, and that by believing you may have life in his name.
many other Gospels Jesus gave commandment to the body of Christ that was said after the resurrection and the saving of disciples.
Paul said Jesus spent 40 days with them ( the disciples) after He rose from the dead and was seen by 500 eyewitnesses those 500 they were not saved? Paul said many who are with us today.
1cor chapter 15.