Wherefore seeing we also are compassed about with so great a cloud of witnesses, let us lay aside every weight, and the sin which doth so easily beset us, and let us run with patience the race that is set before us,
Mary R. Durham, April 2016, LDS General Conference
What is the scriptural or historical context of this scripture:
Paul is writing to the saints again. As an apostle he is calling the saints to repentance and exhorting them to be better.
This scripture makes me recall Alma's response to Korihor in, Alma 30:44 "all things denote there is a God" during his requesting a sign to convince him of the existence of God. Paul is asking us to forsake our sins and try to become better as we have already professed a belief in God and Christ.
Thoughts about this scripture:
"cloud of witnesses" is an interesting term to use. And being "compassed about" means that we are surrounded. So if you are surrounded by a cloud, its not just in every direction, but also above and below, so that there isn't any place to look that doesn't witness and testify of Christ.
Sometimes people feel that faith and business or faith and science are not compatible. But Paul is saying that they are not only compatible, but that they will support a faith in Christ. I think this is a unique perspective that has been lost to many people.
This is not to say that I have my faith in Christ to be informed or modified by modern science or business practices or other worldly things, but my faith and testimony of my savior are re-enforced and strengthened by the world in which I live. Even when this is only accomplished by the worlds opposition to my faith in Christ.
How does this strengthen my testimony
There is a quote that I have always enjoyed. "I believe in Mormonism like I believe the sun has risen. Not because I see it, but because by it I see."
Like this quote, our faith in Christ doesn't come from seeing him, but by how our faith in Christ allows us to see everything else. Seeing the world through the eyes of faith puts everything into two categories. First, those things that I see testify of Christ and his atonement. And second are those things that I don't understand how they testify of Christ yet.