Don’t believe your doubts. Believe God’s Word.
Said our Lord: “Whither I go ye know, and the way ye know” (John 14:4).
Said Thomas: “We know NOT whither Thou goest, and how can we know the way?” (John 14:5).
Who was right? Of course our Lord was right. He knows us better than we know ourselves. But Thomas, believing his doubts rather than his Lord, found himself not merely questioning, but contradicting Christ Himself.
The trouble was that Thomas was thinking on a lower level than was our Lord. Thomas was thinking only in terms of locality and method, while our Lord had persons in mind. All through these pre-crucifixion chapters of John, our Lord appears to be occupied with thoughts about His Father, He had not been talking about going to heaven, but of going to the Father (John 13;1; 14:12). Nor had He referred to moral conduct or theological dogma when He said, “the way ye know”. Rather He had referred to Himself, who alone could gain for Thomas an entrance to the Father. “No man cometh unto the Father,” He said, “but by Me” (John 14:6).
So our Lord was right. Thomas did know whither Christ was going: “to the Father.” And he did know Christ, the way. Had Thomas, rather than our Lord, been right, Thomas would have been a lost soul but, only a few hours later, in our Lord’s hallowed prayer to His Father, He was to say: “This is life eternal, that they might know Thee, the only true God, and Jesus Christ, whom Thou has sent” (John 17:3).
We must be careful about criticizing Thomas too severely, for while he was apt to look on the dark side of things he was also ready to give his life for his Lord. Of all the apostles, it was he alone who said, when the Lord proposed to go to Judaea shortly before His crucifixion, “Let us also go, that we may die with Him” (John 11:16).
At our Lord’s resurrection, however, we again find Thomas believing his doubts, in fact, defending them, as he says: “Except I shall… put my finger into the print of the nails, and thrust my hand into His side, I will not believe” (John 20:25). But when, “after eight days,” he was invited to do just that — as he stood in the very presence of Him who is “the resurrection and the life”, he repented the folly of his unbelief and exclaimed, “My Lord and my God!” (John 20:28). source