No we do not believe that you must live a completely sinless life to obtain celestial glory (aka Heaven). If that was the case no one could obtain Celestial Glory for we all sin.  
 
We can never earn our salvation, but those who assume that grace alone saves us are in for a suprise on the Day of Judgment.  
 
Christ told his disciples to abide in his love (or his grace) keep his commandments (or obey him) (See John 15:10. 
 
We are also told in James 2:26 that " ... faith without works is dead ..." 
 
So it is quite clear from the New Testament that we have the requirement of obeying Christ's teachings to show receive his grace.  
 
Now of course no one is perfect, so we know that we will never perfectly follow his example at all times. Christ knows this and knows our hearts and will have mercy on us. So there is not need to be perfect, there is a need to be continually striving towards perfection though! 
 
Thank you for the question! 
 
I hope that my answer helps!

Hi, i appreciate your comment. i'm not sure what to think still. I have always been told that Mormons believe that one is saved by faith along with works, which is very different than being saved by faith alone, evidenced by works. WHich, siting material, would you say the LDS church believes?  
Thanks again

Hi I just sent a question in without my email. I would really like to be emailed about this. Thanks.  
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