The acts of the disciples is a cornerstone in my Christian belief. These people were convinced that Jesus Christ was the son of God and the only way to God. They so believed this that they would rather face imprisonment, beatings, exile, and, in many cases, very unpleasant deaths, than to say that Jesus was not the Messiah. Who would do this if it was not true?? No one would. No one would be stoned, crucified, or beheaded if they were not 100% sure that Jesus was who He said He was and that by following Him they would end up in a place with a peace beyond human understanding.
I read an account of the Watergate break-in the other day. In this account, one of the Nixon Whitehouse insiders said that the brightest and the best worked in the Nixon Whitehouse yet they could not keep the break-in cover-up a secret for even a few months, and none of them were threatened with death. But the disciples kept the truth of Jesus in front of the masses even though they were not only threatened with death but, in many cases, executed. They did not reverse course one little bit. Again, no person would risk their life if they were not 100% sure of something better after death.
Today's reading tells the story of Jesus spending 40 days with His disciples after He rose from the dead. These 40 days drastically changed the disciples' lives. Before these 40 days, they had argued with each other, deserted their Lord, and even lied about knowing Jesus. After these 40 days, with the help of the Holy Spirit, they became a unified voice that consistently gave the same message about Jesus - no matter the hardship with which they were threatened.
Yes, I am convinced that the disciples absolutely knew that Jesus was the son of God. They were not 50% sure, not 90% sure, not 99% sure; they were 100% sure. Their acts demonstrated their knowledge. The steadfastness of the disciples should be a model for all of us.
Wishing you the best in your walk with Christ,