I learned more about the word sincere a few years ago in Institute. Back in the very olden days sculptors used to use wax in their sculptures to hide flaws and make something appear perfect when in actuality it was not. Sin cerae means without wax. There is dispute as to the etymological history on that, but I like to go with it. Because a sculpture without wax is in its most natural state--exactly as it was created with no attempts to cover up mistakes or flaws. There have been no fake attempts to hide what is natural. If we are to be sincere and honest, we cannot cover up our mistakes with lies so that we appear perfect. Each of us is flawed, each of us constantly make mistakes. It is the natural man in us. But that doesn't mean we cannot reach perfection. We, apprentice learners, cannot apply a spiritual wax to ourselves. We don't know how. It is beyond our skills and ability. But our Master Teacher can. His wax is the Atonement. And with it we can one day be the perfect creation that God intends us to be. Yet that can only happen after all we can do and after our every effort
A wholesome tongue a tree of life: but perverseness therein a breach in the spirit.
Let us walk honestly, as in the day; not in rioting and drunkenness, not in chambering and wantonness, not in strife and envying.
2 Corinthians 13:7
Now I pray to God that ye do no evil; not that we should appear approved, but that ye should do that which is honest, though we be as reprobates.
Finally, brethren, whatsoever things are true, whatsoever things honest, whatsoever things just, whatsoever things pure, whatsoever things lovely, whatsoever things of good report; if any virtue, and if any praise,think on these things.
1 Timothy 2:2
For kings, and all that are in authority; that we may lead a quiet and peaceable life in all godliness and honesty.
2 Nephi 33:6
I glory in plainness; I glory in truth; I glory in my Jesus, for he hath redeemed my soul from hell.
And they were among the people of Nephi, and also numbered among the people who were of the church of God. And they were also distinguished for their zeal towards God, and also towards men; for they were perfectly honest and upright in all things; and they were firm in the faith of Christ, even unto the end.
And they were all young men, and they were exceedingly valiant for courage, and also for strength and activity; but behold, this was not all—they were men who were true at all times in whatsoever thing they were entrusted.
Doctrine & Covenants 51:9
And let every man deal honestly, and be alike among this people, and receive alike, that ye may be one, even as I have commanded you.
Doctrine & Covenants 97:8
Verily I say unto you, all among them who know their hearts are honest, and are broken, and their spirits contrite, and are willing to observe their covenants by sacrifice—yea, every sacrifice which I, the Lord, shall command—they are accepted of me.
Doctrine & Covenants 98:10
Wherefore, honest men and wise men should be sought for diligently, and good men and wise men ye should observe to uphold; otherwise whatsoever is less than these cometh of evil.