These are the generations of Jacob: when Joseph was seventeen years old, being a shepherd, he was with his brothers with the flocks, and he was a lad, and was with the sons of Bilhah and with the sons of Zilpah, his father's wives; and Joseph brought evil tales about them to their father. (Bereshis 37:2)
When Jacob sought to dwell in tranquility, the troubles of Joseph sprang upon him. The righteous seek to dwell in tranquility. Said the Holy One, blessed be He, “What is prepared for the righteous in the world to come is not sufficient for them, but they seek also to dwell in tranquility in this world!” (Rashi)
Jacob did not want rest in the way we understand it. His constant exertion of energy in the service of G-d is something we cannot come close to. So what did chazal mean when they said he "sought to dwell in tranquility" ?
I was told from a good source that Rav Moshe Feinstein z'al said that Jacob wanted to rest from Chinuch (education). He figured his children were all going in the right direction based on their former training. He did not need to keep on top of them as much and he could devote more energy to other aspects of his devotion. This is when the problem with Joseph emerged.
Hashem requires us to tap our greater energies to serve Him. As soon as we slack off we can expect trouble. Of cource every person needs to rest in order to have more strength, but its possible that a portion of our lethargy is coming from a lack of appreciation of Hashem's kindness to us or we may be missing in our fear of G-d. I think most of us have a lot more potential energy than we know about.
The Path of the Just Chapter 7 states:
"a man not permit a mitzvah to grow stale, that when the time for its performance arrives, or when it happens to present itself to him, or when the thought of performing it enters his mind, he make haste to take hold of the mitzvah and perform it, and not allow much time to elapse in the interim, there being no greater danger; for each new minute can bring with it some new hindrance to a good deed."