Chayei Sara תרל”א 2

ובמדרש תנחומא לא תירא כו’ כל ביתה לבוש שנים שבת ומילה כו’.
The Medrash Tanchuma compares all the traits in Eshet Chayil to Sara’s deeds. One of them is that she does not fear gehinom for all her house wore garments שנים, which can also be read as shnayim, two. That her household had two mitzvot Shabbos and Mila.
ג”כ כנ”ל שלא תירא מגיהנם ע”י שגברה ההסתר שנק’ שנים כמו חטאיכם כשנים כו’
This too is as discussed above, that she does not fear gehinnom, since she continuously overcame the hiddenness of this world, which is also called שנים. As the pasuk (Yeshaya 1:18) says if your sins will be like crimson – כשנים they will become white as snow.
וענין שבת הוא זה להאיר קדושת שבת בימי המעשה.
And so too the idea of Shabbos is also to bring light and holiness into the days of the week
וכן מילה שנקרא ברית שהוא הארת הפנימיות ולהסיר ערלה דחפיא ברית [כמ”ש בפ’ וירא ע”ש]:
And so too bris milah which is also called a covenant (Shabbos milah and tefillin), is to bring light into the darkness and remove the עורלה the foreskin which covers the bris.
(See Sfas Emes parshas vayeira, so long as Avraham had a foreskin, HaShem appeared to him in a limited fashion).