Jeremiah 8
1. At that time, saith the Lord, they shall bring out the bones of the kings of Judah, and the bones of his princes, and the bones of the priests, and the bones of the prophets, and the bones of the inhabitants of Jerusalem, out of their graves:
2. And they shall spread them before the sun, and the moon, and all the host of heaven, whom they have loved, and whom they have served, and after whom they have walked, and whom they have sought, and whom they have worshipped: they shall not be gathered, nor be buried; they shall be for dung upon the face of the earth.
3. And death shall be chosen rather than life by all the residue of them that remain of this evil family, which remain in all the places whither I have driven them, saith the Lord of hosts.
4. Moreover thou shalt say unto them, Thus saith the Lord; Shall they fall, and not arise? shall he turn away, and not return?
5. Why then is this people of Jerusalem slidden back by a perpetual backsliding? they hold fast deceit, they refuse to return.
6. I hearkened and heard, but they spake not aright: no man repented him of his wickedness, saying, What have I done? every one turned to his course, as the horse rusheth into the battle.
7. Yea, the stork in the heaven knoweth her appointed times; and the turtle and the crane and the swallow observe the time of their coming; but my people know not the judgment of the Lord.
8. How do ye say, We are wise, and the law of the Lord is with us? Lo, certainly in vain made he it; the pen of the scribes is in vain.
What did Jesus say about this?
Matthew 23
1. Then spake Jesus to the multitude, and to his disciples,
2. Saying, The scribes and the Pharisees sit in Moses' seat:
3. All therefore whatsoever they bid you observe, that observe and do; but do not ye after their works: for they say, and do not.
4. For they bind heavy burdens and grievous to be borne, and lay them on men's shoulders; but they themselves will not move them with one of their fingers.
The Mishnah is basic compilation of the Oral law of Judaism; it was written down around 200 CE. However there is another compilation of oral law from that time period which is nearly as authoritative; this is the Tosefta. Rashi (in his commentary on Talmud Sanhedrin 33a) writes that the Mishnah was redacted by Judah haNasi in consultation with members of the Academy, while the Tosefta was edited by Rabbis Hiyya and Oshaiah on their own, thus the Tosefta is less authoritative. In many ways the Tosefta acts as a supplement to the Mishna.
The Oral Law
The Written Law is another name for the Torah. The Oral Law is a legal commentary on the Torah, explaining how its commandments are to be carried out. The Oral Law today is a written law, codified in the Mishna and Talmud. Orthodox Judaism believes that most of the oral traditions recorded in these books dates back to God's revelation to Moses on Mount Sinai. When God gave Moses the Torah, Orthodoxy teaches, He simultaneously provided him all the details found in the Oral Law. It is believed that Moses subsequently transmitted that Oral Law to his successor, Joshua, who transmitted it to his successor, in a chain that is still being carried on (Ethics of the Fathers 1:1).
The Babylonian Talmud is much more complete than the Jerusalem Talmud, and the redaction is much more careful and precise. Still, it is by no means complete. The gemara only exists for 37 out of the 63 tractates of the Mishna. Why did these tractates remain without gemara in Babylonian Talmud? The traditional answer is that the laws of Zeraim and Toharot (except Niddah) had no practical relevance; The agricultural laws were tied only to the land of Israel. In the diaspora these laws simply were of no use. The purity laws (except for family purity) were no longer applicable, because there was no longer a Temple and sacrificial system. One might think then that there would be no Babylonian Talmud gemara on Qodashim - but there is.
During the 9th century C.E., a number of sects arose that denied the existence of oral Torah. These sects came to be known as Karaites (literally, People of the Scripture), and they were distinguished from the Rabbanites or Rabbinical Judaism. The Karaites believed in strict interpretation of the literal text of the scripture, without rabbinical interpretation.They believed that rabbinical law was not part of an oral tradition that had been handed down from G-d, nor was it inspired by G-d, but was an original work of the sages. As such, rabbinical teachings are subject to the flaws of any document written by mere mortals.