Scripture Insight: D&C 29:34-35

34 Wherefore, verily I say unto you that all things unto me are spiritual, and not at any time have I given unto you a law which was temporal; neither any man, nor the children of men; neither Adam, your father, whom I created.

35 Behold, I gave unto him that he should be an agent unto himself; and I gave unto him commandment, but no temporal commandment gave I unto him, for my commandments are spiritual; they are not natural nor temporal, neither carnal nor sensual.

From the Doctrine and Covenants and Church History: Gospel Doctrine Teacher's Manual: Lesson 14: The Law of Consecration:

Explain that the principles of the law of consecration have not changed since it was revealed through the Prophet Joseph Smith. However, the application of those principles changes from time to time.  The current prophet helps us understand how to apply these principles in our day.

Discussion
I was studying the Sunday School one week in preparation for Sunday and came across the above scripture. I had to stop and take a step back for a moment to more fully comprehend it because something was not adding up for me. Now I know the scripture is true because it was revelation received for these latter days and is included in the canonical works of the church. I have a strong testimony of that. So I know if there is any discrepancy with these and other teachings, the fault is on me and my lack of understanding.

But I confess I was perplexed at first with the scripture. I understood the principle it was outlining perfect. My difficulty came in the history of its application which when looking at the surface level of the evidence seems to contradict it (i.e, changes with Blacks receiving the priesthood, the support and then non-support of polygamy, etc.). Again, because I know the scriptures to be true that this could not be the case.

I decided to return to the manual and continue studying so my mind could wrestle with that one in the background. No sooner do I return to studying the manual do I come across the second bit which is also included above. These made it abundantly clear where my lack of understanding was. What seemed like a contradiction in statement is perfectly explained in three simple sentences (one really if you look at the highlighted portion).