Rav Hirsch of Rimanov zy”a (Sefer Beeros Mayim) writes that this pasuk can be understood to be hinting that the head of every Jew should be lifted up in the sense that everyone should feel confident and proud. One should not become depressed because he knows that he sinned in the past.
Even if one has done bad things, he should accept upon himself not to do it again and to only serve Hashem with joy from then on. By doing this, he will be forgiven for all of his past sins.
A Good Kabalah Saves From Depression:
When a person feels that he is too sad and depressed to serve Him properly, the best thing to do is to accept a good kabbalah upon himself. He should accept to no longer commit the aveiros he did in the past and to try as hard as he can to do everything properly. This should be a great cause of joy that should allow him to serve Hashem with simcha.
It is related that a chasid once came to the Lechovitcher Rebbe zy”a and said that he feels like he is stuck in the “blatte” (mud), and he sees no way of escaping. The Rebbe replied, “Mud is thickest and stickiest when no water is added to dilute it, and such mud will end up crying out completely!”
In this vein, the Bais Aharon of Karlin zy”a once told his chasidim, “I am prepared to accept upon myself all of your aveiros that you committed in the past. The main thing is that you be good from now on!”
He was teaching them not to fall to despair because of their past sins. He encouraged them by telling them to look towards the future and to accept to be good from now on, rather than worrying about the past and feeling sad about their past indiscretions.
Shabbos Doesn’t Want a Depressed Guest:
There once was a chasid who was known to always be sad and depressed. This man once came on a Motzoei Shabbos to his Rebbe, Rav Bunim of Peshischa zy”a, and he sadly related that he had been on the way to spend Shabbos with the Rebbe but he got held up by various obstacles and was unable to get there on time. He was forced to spend Shabbos in alone, in a forsaken place. Understandably, it was not a pleasant or uplifting Shabbos like the one he would have experienced with the Rebbe.
The Rebbe realized that now was the time to rebuke the man for his constant sadness. He told him, “Shabbos is the most accommodating host. When Rosh Hashanah falls out on Shabbos, Shabbos welcomes its guest warmly and gives up the Haftorah and Tefilas Mussaf to accommodate it. The same is true for every yomtov – Shabbos gives its guest the tefillos and Kriyas Hatorah. When Yom Kippur falls on Shabbos, Shabbos even gives up the seudos to accommodate it. But if Tisha B’Av falls out on Shabbos, Shabbos is unwilling to accommodate it, and it does not give up anything for it. Rather, it forces it to wait until Sunday. Why? Because Shabbos will not accommodate a ‘depressing guest’. Instead, it tells it to wait until Sunday.”
