Not LDS - Question about Temple Recommends, Salvation, and the Celestial Kingdom

I am a Christian and not a member of the LDS church, but I have heard online about something called a temple recommend. From my understanding, LDS people go through a meeting with their bishop to receive a "temple recommend" card to be allowed to the temple and thus this fulfills obligations to make it into the celestial kingdom. The bishop asks you things such as, have you been wearing your garments? Have you been paying your tithing? Have you drank any coffee? Have you been watching any pornpgraphy?

As a Christian , I believe that we all sin everyday, whether that be small things like white lies, holding a grudge, being envious, or more grievous sins. However, I believe that Jesus died for my sins and my belief in that will let me go into heaven. It confuses me how a bishop (not God) could deem someone "unworthy" based on the answers to those questions to go into the temple thus be not able to get the highest level of heaven? Even the LDS website says :"The only way to salvation is through faith in Jesus Christ", how can that be true when the requirements to get to the celestial kingdom are to be deemed worthy by a bishop through a temple recommendation? I mean this question in all respect to your beliefs and just coming from a place of curiosity :)