All this could be cleared up if Jesus Christ would simply release His birth certificate, signed and sealed by His Father and mother.
Or would it? How would doubters know that the signatures were authentic? If witnesses were produced, how would skeptics know whether the witnesses were not deceiving or being deceived themselves? If disbelievers could travel back in time, and shadow Mary and Joseph 24 hours a day for the year prior to Jesus' birth, would that be enough to convince them, or would there always be room for alternative explanations?
If there is always potential for alternative explanations, how then can we certify Jesus' birth?
We can't. But His Father can. Heavenly Father is omniscient, so he knows every possible alternative, and knows the truth beyond the possibility of doubt. And he has the unique ability to put His assurance directly into our hearts. Because the logic and reason of man is limited to what is already known, there is no way to know the truth with certainty unless, like Peter the Apostle, we gain our knowledge from One who knows all.
To those who want certification of birth, I invite you to ask for it.