The Hasidic Rebbe Pinchas Shapiro of Koretz once said:
“A Jew should always be happy. God cannot come near a gloomy person, nor can a Tzakik develop closeness with someone who is somber or morose.” Here, then, is another reason for joyous living. Someone habitually morose will turn away countless encounters with others, encounters that no doubt possessed the potential to significantly enrich his or her life. Joy thus opens the door for others, allowing them to approach us and us, in turn, from benefiting from their talents, wisdom and insight. A morose person never even realizes the opportunities he or she has lost.