My neighbor recently asked me if I’d start running with her early in the mornings. “I see that you also like to run,” she told me, “Can I join you? I’m determined to get in shape in 2018. It’s my new year’s resolution – I’m going to starting running four mornings a week.” My neighbor is an evangelical Christian from Texas, and she takes her Gregorian new year very seriously. I can’t remember that last time I made a new year’s resolution – I tend to think about self-improvement primarily in Elul, and rarely in late December. But I’ve been learning Masechet Shevuot, which is all about oaths, and with the start of 2018 I find myself thinking about everything I am tempted to take upon myself or to swear off, and how I might go about doing so.

First and foremost, I think about sleep. Far too many nights a week I stay up long past midnight reading or working (or pretending to work, since it’s hard to concentrate at that hour) – even though I know that I’ll have to be up early with my children. I have tried to set alarms to encourage myself to go to bed, but somehow it never seems to work. I relish the late hours, when time stretches ahead of me endlessly; I feel much more creative when I know I have no deadline, and can write or think for as long as the spirit moves me. But everyone needs sleep, as Matthew Walker has just reminded us in his compelling new book about the effects of poor sleep habits on our health, happiness, and longevity. Even the rabbis knew how important sleep was; they note in masechet Shevuot (25a) that if a person takes an oath that he won’t sleep for three days, we give him lashes and make him go to sleep immediately, since this is clearly a vain oath that can never be fulfilled. Nearly every morning when my kids climb into my bed before 6am, I essentially take an oath to go to bed earlier that night. And then inevitably when I am still at my computer at midnight, I violate that oath. So perhaps the time has come to take my oaths more seriously.

Then there are the oaths that affect others as well. The rabbis note in masechet Shevuot (25a) that oaths that affect other people are taken just as seriously as oaths that affect only oneself. And so if a person says, “I swear I will give a pledge to my neighbor,” this oath is as binding as if he says, “I swear I will throw a rock into the ocean” – even though the former is dependent on his neighbor as well as on himself. Perhaps the rabbis are trying to remind us that even though some oaths may seem to be more dependent on others, in fact all our actions affect other people directly or indirectly. I may think that in staying up late, I am merely making myself more tired, and so I can just suffer the consequences of my decisions. But in it is not just I who suffer when I stay up late: I have less energy to spend time with my kids in the morning, and I am more irritable with them in the evenings when it is time for them to go to bed, and my work suffers, and I am less present and receptive to my husband and friends. When I have slept well and eaten well and I am at ease, my household is calm and my kids are happier. Perhaps this is why the rabbis teach in Nedarim—the tractate of the Talmud that deals with vows—that a husband is authorized to annul any vows that his wife makes that cause her self-affliction. When a wife is suffering, inevitably her whole family suffers as well. It’s not fair to snap at my kids because I’m too tired to be patient with them; I need to get more rest so that my husband and children can have the quality time with me that they deserve.

The rabbis speak often in Nedarim about vows and that deny another person benefit. “Any benefit that my wife might derive from me is forbidden to me like a sacrifice,” a man might swear, thereby denying his wife food and sex and financial support. But as I have come to realize, deriving benefit from others is not something we can necessarily swear off. All of my actions affect those around me, and the way I treat myself affects the way I treat those I love. All too often I am tempted to dismiss self-care as an unnecessary indulgence; I can stay up too late, or skip breakfast, or get by without that cup of coffee I am craving. But when I take care of myself, I am taking care of others. When I benefit myself, I am benefiting others. And so yes, I may start running with my neighbor, because running makes me feel healthy and fit and it’s more fun to run with someone else. But it’s complicated. I’m not taking any oaths about how regularly I’ll run, and I’m making any commitments to myself or to her. When my kids climb into our bed before dawn to snuggle, I don’t want to jump out of bed because I promised my neighbor I’d meet her at dawn. I want to fall back to sleep with my daughter in my arms, and my other daughter hanging on to my back, deriving benefit from the warmth of their little bodies and knowing that they are deriving benefit from  me too.