In Acts 1:3 we read that For 40 days off and on Jesus would appear to them. The word here rendered “seen” is the word in which we get our word ophthalmologist or eye doctor. Luke declares that the disciples eyeballed Jesus staring at Him.
Jesus spoke to them again about the reign He would have over the hearts that trusted in Him.
Those were the “many infallible proofs” of Him being alive after His suffering. You know what? They are the same proofs today that He is alive in the hearts of those that profess His name. You can see Him alive today as He has chosen you and I to go and do what He did. You can see Him alive in the fact that we are empowered to do this. You can see Him alive when you look at one of His followers because they look like Him. Lastly you can see Him alive in the fact there are changed lives everywhere where people have opened up their hearts to Him!