(Kahou wa nete mate; “For good fortune, sleep, wait.”)
Good fortune will come of its own accord, in its own time, so it’s best to prepare and patiently wait for it rather than fretting or trying to force things. There are limits to what any of us can do with our own power, so it’s best to do what you can and then let things run their course. Good things come to those who wait.
We begin with the noun 果報 (kahou), which translatable as “good fortune” or “happiness,” but in a more literal reading (“fruit reward” or “fruit news”) we see its Buddhist meaning of Vipāka, that is, karmic payoff. (Cf. 因果応報.) This load term is marked as the topic of discussion by the particle は (wa), and the comment on this topic is an admonition: the verb 寝る (neru), “to sleep,” in conjunctive form (as simply 寝, ne), taking the suffix つ (tsu), itself in conjunctive form as て (te); this structure as a whole is being used to mark a connected series of verbs. This “series” is rounded out by 待つ (matsu), “to wait,” in imperative form.
Replacing 果報 with homophone 家宝 (“heirloom,” literally “family treasure”) is an error. Variant phrases may replace it with 運 (un, “luck”) or 福 (fuku, “good fortune”), however. Compare and contrast 待てば海路の日和あり and 蒔かぬ種は生えぬ (alternately, this….)
Keep in mind that just waiting is not recommended; this proverb simply reminds us that you don’t always see the fruit of your labor or deeds right away. One should do all necessary (or possible) work, but then calmly wait for the payoff instead of wasting energy by stressing over it.
This saying is attributed to our friend, the poetic collection 『毛吹草』 (Kefukigusa). Perhaps surprisingly, it is the く (ku) entry of the Osaka iroha karuta set, because 果 used to be pronounced kwa (rendered as くゎ in modern orthography) – cf. terms like 怪談 as kwaidan.
(“Un? Reisei ja nai ka, nyuugaku shiken no kekka no houkoku wo matteru wari ni. Kinchou shinai no ka?” “Kinchou shite mo kekka wa kawaranai ja nai ka. Isshoukenmei benkyou shite shiken de yarikitta to omou kara, ato wa kahou wa nete mate dake sa.”)
[“Hm? You’re awfully chill, for someone waiting on the results of their entrance exams. Aren’t you nervous?” “How would being nervous help? I believe that I studied as hard as I could, and followed through on the test itself, so after that it’s just a matter of waiting for my work to bear fruit.”]