Inner And Outer Keys
בפרשת ועתה מה ה"א שואל כו' דאיתא בגמ' מי שיש בידו תורה ואין בידו יראת שמים דומה למי שנמסרו לו מפתחות פנימיות ומפתחות החיצוניות לא נמסרו בידו
On the parsha that begins "And now, what does Hashem ask of you," the Gemara teaches that one who has Torah in his possession but does not have yiras Shamayim in his possession is like a man to whom the keys of the inner chambers were handed over, but the keys of the outer chambers were not handed over to him.
The pasuk asks what Hashem requests of a person, and the Sfas Emes opens with the Gemara's mashal: Torah without yiras Shamayim is like being given the inner keys while lacking the outer keys, leaving one unable to actually enter.
והנה מרע"ה הוריד התורה לבנ"י והכין לפניהם שער הפנימי ולא נשאר בעבודת האדם רק מפתח החיצוניות לפתחו בכח היראה
Now, Moshe Rabbeinu brought the Torah down to Bnei Yisrael and prepared the inner gate before them, so that there remained in a person's avodah only the outer key, to be opened through the power of yirah.
Moshe Rabbeinu gave Bnei Yisrael the Torah, which is the inner gate already prepared for them; all that is left for a person to accomplish on his own is the outer key, which is unlocked through yiras Shamayim.
והתורה היא מתנה בלבו של אדם כדאיתא במד' וארא
And the Torah is a gift in the heart of a person, as is brought in the Midrash on parshas Va'eira.
The Torah is implanted within a person's heart as a Divine gift, as the Midrash on Va'eira indicates.
והיא בחי' הנשמה
And this is the aspect of the neshamah.
This inner gift of Torah corresponds to the neshamah within a person.
ויראה היא תיקון הגוף להיות כלי לקבל הארת הנשמה
And yirah is the rectification of the body, so that it should become a vessel to receive the illumination of the neshamah.
Yirah works on the body, refining it so that the physical self can become a fitting vessel to hold the light of the neshamah.
ואמר ועתה
And therefore it says "And now" (ve'atah).
The word "now" signals a shift in time, pointing to the change that came about after the cheit.
כי קודם החטא הי' גם היראה מתנה כמ"ש למען תהי' יראתו ע"פ
For before the cheit, yirah too was a gift, as it is written, "so that His fear shall be upon your faces" (Shemos 20:17).
Before the cheit of the eigel, even yirah came to a person as a free gift, as the pasuk says Hashem's awe would rest upon them.
ואחר החטא שנתלבשו בחומר צריכין למפתחו' החיצוניות
But after the cheit, when they became clothed in coarse physical matter, they require the outer keys.
After the cheit, when people became wrapped in coarse physicality, yirah no longer comes freely, and a person must labor to acquire the outer keys himself.
שמקודם היו כלם בענים כמ"ש אמרתי אלקים אתם
For beforehand they were all in the aspect of the upper realms, as it is written, "I said: you are godly beings" (Tehillim 82:6).
Before the cheit, Bnei Yisrael stood on an elevated, almost angelic level, as the pasuk calls them godly beings.
ובש"ק יש הארה מלוחות הראשונות
And on the holy Shabbos there is an illumination from the first Luchos.
On Shabbos there shines a glimmer from the first Luchos, the level that existed before the cheit.
לכן אפי' ע"ה אימת שבת עליו ונפתח בו שער הפנימי הפונה קדים שהוא מוכן רק אחר פתיחת החיצוניות כמ"ש אשר צפנת ליראיך:
Therefore, even an ignorant person has the awe of Shabbos upon him, and the inner gate that faces eastward is opened within him, that gate which is prepared only after the opening of the outer one, as it is written, "which You have hidden away for those who fear You" (Tehillim 31:20).
Because of that Shabbos illumination, even an unlearned person is overcome by awe of Shabbos, and the inner gate opens within him on its own, even though normally that gate can be reached only after one has first opened the outer gate through his own yirah, as the pasuk speaks of the good hidden away for those who fear Hashem.
Summary: The Sfas Emes builds on the Gemara that Torah without yiras Shamayim is like holding the inner keys but lacking the outer ones. Moshe Rabbeinu already gave Bnei Yisrael the inner gate, the Torah, which is the neshamah's gift implanted in the heart; what remains for a person is to acquire the outer key of yirah, which refines the body into a vessel for the neshamah's light. Before the cheit, yirah too came as a free gift, since Bnei Yisrael stood on an exalted level, but once they became clothed in coarse matter they must toil for the outer keys themselves. On the holy Shabbos, however, an illumination from the first Luchos shines forth, so that even an ignorant person is filled with awe of Shabbos and the inner gate opens within him on its own, a gate normally reached only after one's own opening of the outer gate.