In the Sefer Ner Mitzvah V’Torah Ohr, in the section called Shaar HaYichud by the hailige R’ Dov Ber from Chabad, known as the Mittler Rebbe zt’l, we can learn an amazing Sod (secret) in avodas Hashem. In all Torah we can learn how to better serve Hashem, but this particular piece is amazing.
The Mittler Rebbe teaches us that there have to be two separate aspects to attaining high levels in avodas Hashem: bechiya (crying) and chedva (rejoicing). For the crying he brings that one should be careful to say Tikkun Chatzos and mourn over our separation from Hashem, which is the primary character of this form of sadness; and that we should be certain to daven and do all the mitzvos every day with great joy. He says there that as close as we get to the main thing, that being the Ohr Ain Sof (Light of the Limitless), so too do we become more immersed in the opposite; therefore as the Ohr Ain Sof is pure spiritual joy, so does attempting to come closer remind us of our lowliness and distance from Hashem, leading to crying from sadness at this and bitterness of the soul. He says there a very sharp remark that someone who only has one or the other, absolute joy or absolute sadness, has done absolutely nothing in coming closer to God and will in fact completely lose all his accomplishments and sever his connection he has attained thus far, chas v’sholom.
The reason I share this is because it is important to remember that we have to have both aspects in our avodah: that of crying and of rejoicing. The Baal Shem himself says in Keser Shem Tov that one should never cry from anything but great simcha or d’veikus (cleaving to Hashem). Rebbe Nachman teaches that we must always be happy, but also broken-hearted. This may seem to be a contradiction but ultimately it isn’t at all.
It says in Tehillim that Hashem is close to the broken-hearted. Therefore, through feeling broken and in pain due to feeling distant from Hashem we ultimately come even closer to Him. The state of sadness is in the aspect of Din, and that of joy in Chesed. Through experiencing both states, and realizing them as an aspect of Hashem’s world and an integral part of His service, we perform a huge Yichud (Spiritual unification) in the worlds above, which brings us personally as well as the entire world to a higher spiritual level. The truth is that only through experiencing the full range of human emotion can we really attain anything in coming closer to Hashem and cleaving to Him in truth. The key piece of advice that the Mittler Rebbe, as well as his father the Baal HaTanya, teach us is to partition times for each thing: Tikkun Chatzos is for being sad, the rest of the time should be devoted to serving Hashem with great joy.