笑う門には福来る
(Warau kado ni wa fuku kitaru; “Good fortune comes to laughing gates.”)

Definition:

Fortune and happiness, or good luck, come to the homes of those who are always smiling and laughing. A positive attitude attracts positive events. Life is better when you face it cheerfully.

Breakdown:

笑う (warau) is “to laugh” or “to smile”; here the verb directly modifies the following noun 門 (kado), “gate” or “doorway,” especially the gates of an estate or the front door of a house, and metonymically signifies the household as a whole. に (ni) is a directional or locational particle and は (wa) is the topic-marker particle. Here, the combination means that は takes on an emphatic or contrastive function, implying that other gates do not draw good fortune in the same way.

And we end our saying with another noun-verb pair: the noun 福 (fuku) is “fortune,” “luck,” and the verb 来る (in this case kitaru rather than the more common kuru) is “to come,” “to arrive.” The nuance of the unusual form is that of an action that is completed or continued, rather than being as yet unfinished.

Notes:

Some versions of this saying do without the emphatic は; others generalize 門 to 所 (tokoro, “place”) and swap に for the directional particle へ (e).

Pronouncing 門 as mon or writing kado as its homophone 角 (corner, angle) is incorrect.

This saying can be found in the Kyoto iroha karuta set.

Example sentence:

「そんな暗い顔をしてては駄目、笑う門には福来るよ」

(“Sonna kurai kao wo shitete wa dame, warau kado ni wa fuku kitaru yo.”)

[“Don’t look so gloomy! A smile brings good luck!”]