After the Lord Jesus rose from the dead, He had 40 days of showing himself to His disciples before He ascended to heaven. I would like to draw your attention to the portion which say, "by many infallible proofs". This means Jesus provided irrefutable proofs to the disciples that He was alive. This was part of strengthening their convictions and faith. They needed to have the proof beyond doubt because they were to continue the preaching without Jesus being physically with them. During the forty days, He had series of appearances to the disciples so all could see Him. One evening He suddenly appeared to them as they met within closed doors for fear of the Jews. John 20:20 reports on that meeting stating "And when he had so said, he shewed unto them his hands and his side. Then were the disciples glad, when they saw the Lord". He showed the hands and pierced side as part of physical proof that He was the same. One disciple, Thomas, doubted when he was told because he was not around that time. Jesus made another appointment eight days later just for him. After seeing Him, Thomas said, "My Lord and my God" (John 20:28), confirming that truly Jesus was alive. Aside showing His body's marks He also did things that He once had done before His death. For instance He appeared to them while fishing at river Tiberius and they had no catch yet and He told them, "Cast the net on the right side of the ship, and ye shall find" and when they did, they were not able to draw it for the multitude of fishes (John 21:1-7). Verse 7 says, "Therefore that disciple whom Jesus loved saith unto Peter, It is the Lord". They recognized Him because He did what He had done before His death (Luke 5:5-6). This was giving proof beyond doubt to fortify their faith. Do you know just like Jesus was giving proof we are also called to produce proof to the world that Jesus is alive. Acts 1:8 says, "But ye shall receive power, after that the Holy Ghost is come upon you: and ye shall be witnesses (proof producers) unto me both in Jerusalem, and in all Judaea, and in Samaria, and unto the uttermost part of the earth". As Jesus provided proof, today you are commissioned to produce proof by the Spirit that Jesus is alive. This is a noble responsibility.