Behold, I shew you a mystery; We shall not all sleep, but we shall all be changed, In a moment, in the twinkling of an eye, at the last trump: for the trumpet shall sound, and the dead shall be raised incorruptible, and we shall be changed. (1 Corinthians 15:51-52)
For several years now, but more so lately, the soon return of the Lord Jesus Christ, occupies my mind almost constantly – hopefully not to the point that I am so heavenly minded that I am no earthly good. As a matter of fact, the prospect incites a sense of urgency within me to share, or better, to warn, the lost around me, especially my loved ones, of the menacing peril that looms ahead for those left behind when Jesus returns for His Bride, the Church. Anyone rejecting Christ, whether by choice or by ignorance, faces seven years of unimaginable horror on earth, until Jesus returns as King of Kings and Lord of Lords to claim His Kingdom on earth for 1000 years (Revelation 20). During that awful period of seven years, people will still have the opportunity to repent and follow Jesus, but they may have to pay for that choice with their lives.
For believers who share my anticipation, I wonder what our call to “come up hither” (Revelation 4:1) will be like? In the starting verse above, the Apostle Paul says that we, if we are not “asleep,” will “be changed in a moment, in the twinkling of an eye” (1 Corinthians 15:51-52). The Greek word translated moment is atomos, from which we get our English word “atom,” and it signifies the smallest, indivisible amount of time. Paul further defines the “moment” as “the twinkling of an eye.” The twinkling of an eye is faster than “the blink of an eye” which is 100-400 milliseconds. I read somewhere that the “twinkling of an eye” is the amount of time it takes for light to enter the eye, hit the retina, and reflect back out; it is a ridiculously small amount of time.
Paul tells us this event takes place “at the last trump.” John the Revelator, who enjoyed a “sneak preview” of this future event, said, “the first voice which I heard was as it were of a trumpet talking with me; which said, Come up hither” (Revelation 4:1, emphasis mine). Will we hear an actual trumpet call and automatically understand that we are being called home? In another place Paul says that, “the Lord himself shall descend from heaven with a shout, with the voice of the archangel, and with the trump of God” (1 Thessalonians 4:16, emphasis mine). Will everyone on earth hear the sound? Perhaps they will, but only those for whom the call is intended will understand the meaning. I recall that when Jesus called Paul into service, “the men which journeyed with him stood speechless, hearing a voice, but seeing no man,” (Acts 9:7, emphasis mine). In another place Paul says, “they that were with me saw indeed the light, and were afraid; but they heard not the voice of him that spake to me” (Acts 22:9, emphasis mine). The connotation here is that, even though they heard the sound, they did not hear the voice with understanding. The communication was intended solely for Paul and no one else. That is what I think will happen at the Last Trump. Those who are His “sheep” will hear and understand the voice of the Shepherd. The rest may hear something, but not know what it is.
When that call comes, “the dead in Christ shall rise first: Then we which are alive and remain shall be caught up together with them in the clouds, to meet the Lord in the air” (1 Thessalonians 4:16-17, emphasis mine). In the twinkling of an eye, the decayed bodies of all the saints who are “asleep” (i.e., dead) will be reconstituted, and they will burst forth from their graves and take flight to meet Jesus in the air. In that same instant, “we [who are alive] shall all be changed” (1 Corinthians 15:51); in the twinkling of an eye, our bodies will be transformed from mortal to immortal. Will we feel it? What sensation will we experience? Suddenly all aches and pains will cease. Wrinkled skin will return to the firm supple skin of our youth. Grey hair will return to its former natural vibrancy. Heads of skin will be restored to their former glory – without the dandruff! I imagine myself in front of the mirror checking my “gig line.” I look down to check a button I missed, and when I look back up, I am staring at my 30-year old self with a full head of wavy hair! Then in the next moment, my clothes fall off as I pass right through the roof of my house. I look down and watch my house grow smaller and smaller as I zoom skyward like in a Star Wars movie. I look up and see Jesus standing there in space with open arms to welcome me, and I look around me and see millions of others wearing white robes like mine going the same direction I am traveling – toward Jesus. And no one is old. No one is disfigured. No one is bent, broken, or blemished in any way. All those I see are perfect creations like the first pair God made in the Garden of Eden. It will happen in the twinkling of an eye!
Not everyone on earth will go. Behind will be all those who rejected God’s free gift of salvation to face the horrors of hell on earth for the next seven years. Reader, if you have not asked Jesus to be your Savior, you will be included with those who are left behind. Do not let another day go by without asking Jesus to save you. Invite Him into your heart today. In the twinkling of an eye, that matter will be settled, and you can rest secured in His love. Do it now!
 Question posted at https://math.stackexchange.com/questions/48664/how-long-would-it-take-for-light-to-go-through-a-human-eyeball-and-back-to-the-o/, accessed 04/18/2017.