St. Thomas asked Jesus how to know the way to where He would go. Jesus responded with a serious, profound answer. To the next request from St. Philip to show the disciples the Father, however, Jesus did not respond with such a profound answer. Instead, Jesus expressed exasperation.
Why did Jesus respond so differently to the two questions? Possibly it is because of the intentions behind the two requests. Although we can't know the motives of each apostle, the text provides a few hints.
Thomas' question seems to be asked with the intent of knowing the way because he intended to keep following Jesus in whichever direction Jesus moved. Earlier, Thomas advocated following Jesus even to death (Jn 11:16). Jesus no doubt would have been pleased with such obedient devotion, and gave Thomas an answer that has echoed through the centuries: "I am the Way, and the Truth, and the Life; no one comes to the Father but through Me" (Jn 14:6). Philip asked a question that ended with the statement that said if he got what he wanted, that would be "enough" (Jn 14:8).
One man apparently put no limits on what Jesus could do with him; the other man possibly did. Are your requests pleasing to Jesus? Are you putting no limits on what Jesus is permitted to do in your life?