The word halakha is derived from the Hebrew root halakh – "to walk" or "to go". Taken literally, therefore, halakha translates as "the way to walk", rather than "law". The word halakha refers to the corpus of rabbinic legal texts, or to the overall system of religious law.

Halakhah, in Judaism, the totality of laws and ordinances that have evolved since biblical times to regulate religious observances and the daily life and conduct of the Jewish people. Quite distinct from the Law, or the Pentateuch (the first five books of the Bible), Halakhah purports to preserve and represent oral traditions stemming from the revelation on Mount Sinai or evolved on the basis of it. The legalistic nature of Halakhah also sets it apart from those parts of rabbinic, or Talmudic, literature that include history, fables, and ethical teachings (Haggada). That Halakhah existed from ancient times is confirmed from nonpentateuchal passages of the Bible, where, for example, servitude is mentioned as a legitimate penalty for unpaid debts (2 Kings 4:1).

Oral traditions concerning Jewish law passed from generation to generation, and eventually it became apparent that they required organization. The work of gathering opinions and interpretations was begun by Rabbi Akiba in the 1st–2nd century CE and carried on by his disciples, such as Rabbi Meïr. Early in the 3rd century this new compilation, the Mishna, was complete, arranged in its final form by Judah ha-Nasi. Though the Mishna contained the most comprehensive collection of Jewish laws up to that time, it was not meant to settle issues involving contradictory interpretations. Almost immediately, however, Jewish scholars in Palestine and Babylonia began to elaborate extensive interpretations of the Mishna that were called Gemara. When the work was completed several centuries later, the Mishna and the Gemara, taken together, were called the Talmud.

Centuries later, social and economic changes presented new problems of interpretation and required new applications of the law. This gave rise to new compilations of Halakhah by such outstanding scholars as Moses Maimonides in the 12th century, Jacob ben Asher in the 12th and 13th centuries, and Joseph Karo in the 16th century.

Though Judaism acknowledges a continuous development of Halakhah, the law is always viewed as an explication or extension of the original Law given on Mount Sinai. Conservative rabbis tend to adapt certain Halakhahs to fit conditions in the modern world, as, for instance, the Halakhah regarding observance of the Sabbath. Reform Jews tend to disregard Halakhah, though some of them adhere to certain of its precepts.

The subject matter of the oral Torah is classified according to its content into Halakha and Haggada and according to its literary form into Midrash and Mishna. Halakha (“law”) deals with the legal, ritual, and doctrinal parts of Scripture, showing how the laws of the written Torah should be applied in life. Haggada (“narrative”) expounds on the nonlegal parts of Scripture, illustrating biblical narrative, supplementing its stories, and exploring its ideas. 

Deuteronomy 6:4–9, Deuteronomy 11:13–21 and Numbers 15:37–41.

[Deuteronomy 6:4–9]

4 Hear, O Israel: The Lord is our God; the Lord is one.           

5 And you shall love the Lord, your God, with all your heart and with all your soul, and with all your means.

6 And these words, which I command you this day, shall be upon your heart.           

7 And you shall teach them to your sons and speak of them when you sit in your house, and when you walk on the way, and when you lie down and when you rise up.

8 And you shall bind them for a sign upon your hand, and they shall be for ornaments between your eyes. 

9 And you shall inscribe them upon the doorposts of your house and upon your gates.

[Deuteronomy 11:13–21]

13 And it will be, if you hearken to My commandments that I command you this day to love the Lord, your God, and to serve Him with all your heart and with all your soul,

14 I will give the rain of your land at its time, the early rain and the latter rain, and you will gather in your grain, your wine, and your oil.

15 And I will give grass in your field for your livestock, and you will eat and be sated.       

16 Beware, lest your heart be misled, and you turn away and worship strange gods and prostrate yourselves before them.             

17 And the wrath of the Lord will be kindled against you, and He will close off the heavens, and there will be no rain, and the ground will not give its produce, and you will perish quickly from upon the good land that the Lord gives you.                

18 And you shall set these words of Mine upon your heart and upon your soul, and bind them for a sign upon your hand and they shall be for ornaments between your eyes.          

19 And you shall teach them to your sons to speak with them, when you sit in your house and when you walk on the way and when you lie down and when you rise.          

20 And you shall inscribe them upon the doorposts of your house and upon your gates,    

21 in order that your days may increase and the days of your children, on the land which the Lord swore to your forefathers to give them, as the days of heaven above the earth.

[Numbers 15:37–41.]

37 The Lord spoke to Moses, saying:   ר:

38 Speak to the children of Israel and you shall say to them that they shall make for themselves fringes on the corners of their garments, throughout their generations, and they shall affix a thread of sky blue [wool] on the fringe of each corner.          

39 This shall be fringes for you, and when you see it, you will remember all the commandments of the Lord to perform them, and you shall not wander after your hearts and after your eyes after which you are going astray.

40 So that you shall remember and perform all My commandments and you shall be holy to your God.

41 I am the Lord, your God, Who took you out of the land of Egypt to be your God; I am the Lord, your God.