Musar על שבת 207:4

The camp and flag of the tribe of Dan were situated in the North. The name of G–d concludes with the letter ה, symbolizing the charity, i.e. צדקה, of G–d. It is pointed out in the 12th chapter of the Talmud Shabbat, folio 104, that the letters ג and ד in the Hebrew alphabet are short for גמול דלים, dealing kindly with the poor. These letters are followed by the letter ה, a letter of the name of G–d. Not only does the way this letter is formed represent the name of G–d, but if you use the bottom left leg of the letter and place it before what remains, you get יד, hand, an allusion to the hand that should be extended to the poor. There are various symbolic meanings to the manipulation of sections of this letter, amongst others the result achieved is דודי. He who gives charity in the North, i.e. "hidden", anonymously, before G–d, is considered as having chosen a very commendable way of giving charity (The word Tzafon, North, should be read instead as Tzafun, "hidden"). Gold is supposed to have its origin in the North, or "is hidden," not easily accessible. The angel גבריאל, is positioned on the left, i.e. near the camp of Dan. We are told in Midrash Eicha, by Rabbi Joshua of Sachinan, that the angel Gabriel held the coals (symbol of the destruction that would come upon Jerusalem) in his hands for seven years, all the while hoping that Israel would do תשובה. When they failed to do so, he was ready to throw all these coals at Israel in anger and cause the destruction of Jerusalem. G–d called out to him to be careful not to be so indiscriminate, since there were amongst the people those who practised this charity anonymously, [and that is why their good deeds had not come to the attention of Gabriel. Ed.] In the book Shaarey Gan Eden, commenting on Ezekiel 10,8, "There appeared under the wings of the Cherubs the form of a man's hand," this is explained as a reference to this Midrash Eichah we have just quoted. The words "under their wings" is a reference to the hidden nature of these charitable deeds performed by Jews in Jerusalem.