What gives us strength? This week's Portion, VaYetze, starts with the famous dream of Jacob's ladder. Jacob hears there wonderful promises about his future and about the future of the People of Israel. He gets up from there, and then the Torah says: "וַיִּשָּׂא יַעֲקֹב רַגְלָיו וַיֵּלֶךְ", ("And Jacob carried his legs and went..."). Rashi explains: Since Jacob was given good news - his heart carried his legs, and it became easy for him to walk. That is, thanks to the things that Jacob heard - it was not his legs that were walking, but his heart that was lifting his legs.
A few verses later, again we see the mind's ability to affect the body and give it special forces. Jacob moves a heavy rock, that would normally take many people to lift from the top of the well. He did not only hear in his dream good news about his important future role, but also saw Rachel, his partner in fulfilling this role, for the first time.
And perhaps we can learn from this what are the two most important things that can affect a person positively more than anything else, giving him strength and lifting him up: faith and one's spouse.