Some people demand proof of the existence of Jesus Christ so that they can have "believe". The Lord could easily provide proof but that would not teach us faith. Later in Ether 12, Moroni teaches us "ye receive no witness until after the trial of your faith. Why do you think that is? Why is it so important for us to learn faith first and be rewarded with a witness after?
It might have to do with the fact our Savior loves us and wants to to be happy. Happiness comes in service to others and faith gives us power to do all things necessary to help our fellowman. In Moroni 7 we read "Christ hath said: If ye will have faith in me ye shall have power to do whatsoever thing is expedient in me." What is more expedient in Christ than service to our fellowman?
Ether 12
10 And he answered: Nay; Lord, ashow thyself unto me.
11 And the Lord said unto him: aBelievest thou the words which I shall speak?
12 And he answered: Yea, Lord, I know that thou speakest the truth, for thou art a God of truth, and acanst not lie.
