2 Corinthians 3

As we are taught today that every member is a missionary, Paul wrote to the Corinthians -

"Ye are our epistle written in our hearts, known and read of all men:
3 Forasmuch as ye are manifestly declared to be the epistle of Christ ministered by us, written not with ink, but with the Spirit of the living God; not in tables of stone, but in fleshy tables of the heart."  (New Testament | 2 Corinthians 3:2 - 3)

Which suggests to me that we are examples of Christ-like living in everything we do.  Which also suggests that the world is watching.  It reminds me of the words of Alma to his son, Corianton -

"...for when they saw your conduct they would not believe in my words."  (Book of Mormon | Alma 39:11)

In our conduct, we are not only to live the letter of the law, but also the Spirit of the law -

"Who also hath made us able ministers of the new testament; not of the letter, but of the spirit: for the letter killeth, but the spirit giveth life."  (New Testament | 2 Corinthians 3:6)

I'm sure Paul is referencing the "letter" as the law of Moses, which in itself cannot bring eternal life.  Thus the wording "the letter killeth".  Paul explains -

"But even unto this day, when Moses is read, the vail is upon their heart.
16 Nevertheless when it shall turn to the Lord, the vail shall be taken away.
17 Now the Lord is that Spirit: and where the Spirit of the Lord is, there is liberty.
18 But we all, with open face beholding as in a glass the glory of the Lord, are changed into the same image from glory to glory, even as by the Spirit of the Lord."  (New Testament | 2 Corinthians 3:15 - 18)