The Rambam (Hilchos Chanukah 4:12) writes, "The mitzvah of lighting Chanukah licht is an extremely beloved mitzvah, and a person must be cautious with it." Why are Chanukah licht called a mitzvah chaviva meod, an extremely beloved mitzvah? We will explain with a mashal:
There was a poor girl who married a very wealthy man. She felt honored to live in the large mansion. She had never lived amidst so much wealth before. But one day, she told her husband that she preferred her old, humble home, where she lived before she got married. The husband agreed to move to his wife's old home to please her. The wife was overjoyed since now she knew that her husband loved her. She enjoyed a better lifestyle when they lived in the mansion, but she thought: "He brought me to his fancy home because he lives there. Where else should he bring me? This doesn't prove that he loves me." But when she saw that her husband was prepared to forgo pleasure and comfort to please her, that assured his love to her.
That is why the Rambam calls Chanukah licht a very beloved mitzvah. It is very special because on Chanukah, Hashem comes down to our low levels to raise us, proving that He loves us. He comes down to us to elevate us so that we can be close to Him.
The Meor Einayim writes, "The Shechinah never descends below ten tefachim (see Succah 5). However, Hashem makes sure that no Jew will be detached from Him. So, during the miracle of Chanukah, Hashem kiveyachol comes down below ten tefachim. He comes close to man to bring him back up to Him."
The Divrei Chaim of Sanz zt'l said, "On Shabbos, Hashem brings us up to Him. On Yom Tov, Hashem comes down to us. On Chanukah, Hashem visits His children in prison." It is the holiday for the people imprisoned by the yetzer hara and distant from Hashem's presence. On this holiday, Hashem comes to them.
The Divrei Chaim of Sanz zt'l explains, "When a king is on his throne in his palace, the average person can't visit him. Surely, those being punished by the king won't be able to visit the king. However, when the king travels around his kingdom, it's his custom to visit the prisoners in jail. At this time, the prisoners shout, ‘King! Save us!' This is what happens on Chanukah. Hashem comes to us to save us from our imprisonment."
One night, before lighting Chanukah licht, the Tolna Rebbe zt'l asked a chassid who had a short wife, "When you speak to your wife, does she climb up on a chair to speak to you or do you bend down to speak with her?" After asking this question, the Rebbe lit the Chanukah licht.
Rebbe Mordechai Dov of Hornesteipel zt'l explained the Tolna Rebbe's intention. The Gemara (Bava Metzia 59.) says, "If you have a short wife, bend down to seek her counsel." The Tolna Rebbe hinted that on Chanukah, Hashem keviyachol bends down to whichever level we are on to elevate us.
The Sfas Emes writes, "Chanukah is mostly for the chalashim and the beinonim." Chanukah is mainly for the Yidden who are at a low or mediocre level. Chanukah is their opportunity to come close to Hashem.