Uniting Thought Speech Deed

בפיך ובלבבך לעשותו הוא כלל האדם מחשבה דיבור מעשה

"For it is in your mouth and in your heart, to do it" (Devarim 30:14) — this encompasses the entirety of man: thought, speech, and deed.

The Torah locates avodas Hashem in mouth and heart, which together with action make up the three faculties of a person: thought (heart), speech (mouth), and deed.

וכשאדם מחבר אלה הג' מתדבק ג"כ בשורש התורה כי כמו שיש בפרט כן בכללות בנ"י הם הדיבור והמצות המעשה והתורה המחשבה לכן הכל תלוי באדם

And when a person joins these three together, he likewise becomes attached to the root of the Torah; for just as it exists in the individual, so too in the whole of Klal Yisrael — they are the speech, and the mitzvos are the deed, and the Torah is the thought — therefore everything depends upon man.

When a person unites his thought, speech, and deed, he connects to the very root of the Torah; the same triad exists in Klal Yisrael as a whole, where Bnei Yisrael correspond to speech, the mitzvos to deed, and the Torah to thought — so the entire structure rests on man's effort to unify them.

וכ' הנסתרות כו' והנגלות לנו כו' לעשות את כ"ד התורה כו'

And it is written, "The hidden things belong to Hashem our God, but the revealed things belong to us and to our children forever, to fulfill all the words of this Torah" (Devarim 29:28).

The Sfas Emes brings the pasuk that draws a line between the hidden matters, which are Hashem's domain, and the revealed matters, which are entrusted to us to carry out the whole Torah.

א"כ נראה שגם הנסתרות בידינו ע"י שיודעין שהנסתרות נתלים בהנגלות

If so, it appears that even the hidden things are within our grasp, through the awareness that the hidden things are bound up with the revealed things.

Even though the hidden things seem beyond reach, they too are accessible to us, because the hidden is tied to and reached through the revealed deeds we can do.

ומדבקין כל המעשים בשורשם עי"ז מתקיים לעשות כ"ד התורה גם הנסתרות כנ"ל:

And by attaching all of one's deeds to their root, through this is fulfilled "to fulfill all the words of this Torah" — even the hidden things, as explained above.

By binding all his actions back to their source, a person thereby fulfills the entire Torah — reaching even the hidden dimension through the revealed mitzvos he performs.

Summary: The Sfas Emes opens from the pasuk "For it is in your mouth and in your heart, to do it," which contains the whole of a person — thought, speech, and deed. When a person unifies these three, he becomes attached to the root of the Torah, for the same triad is found in Klal Yisrael as a whole: Bnei Yisrael are the aspect of speech, the mitzvos the aspect of deed, and the Torah the aspect of thought, so that everything depends on man. He then ties this to the pasuk distinguishing the hidden things, which belong to Hashem, from the revealed things, which are given to us to fulfill the whole Torah. His chiddush is that even the hidden things lie within our reach, since they are bound up with the revealed deeds — and by attaching all our actions to their root, we fulfill the entire Torah, even its hidden dimension.