Classical Hebrew is the term used for the archaic form of the Hebrew language in which the Holy Bible was originally written. The language flourished between the 12th and 6th centuries Before Christ. The term also may include all pre-medieval dialects of Hebrew, including Mishnaic Hebrew.
Classical Hebrew may be subdivided by four eras:
(i) Archaic Hebrew – the oldest form of Classical Hebrew, Archaic Hebrew, also known as Old Hebrew or Paleo-Hebrew, is the oldest stratum of Biblical Hebrew, corresponding to the spoken language of roughly the 10th to 9th centuries BC, or the early Monarchic Period. It is found in poetic sections of the Bible and inscriptions dating to around the 1000 BC. The oldest known artifacts of Archaic Hebrew are various Biblical accounts from the Hebrew Bible, including the Song of Moses (Exodus 15) and the Song of Deborah (Judges 5). Biblical poetry uses a number of distinct lexical items, for example חזה for prose ראה (see), כביר for גדול (great). Some have cognates in other Northwest Semitic languages, for example פעל (do) and חָרוּץ (gold) which are common in Canaanite and Ugaritic languages. Archaic Hebrew is distinguished from Standard Biblical Hebrew that is used in most of the Hebrew Bible (8th to 6th century BC), and from Late Classical Hebrew (5th to 2nd century BC).
(ii) Standard Biblical Hebrew – later pre-exilic Hebrew such as is found in prose sections of the Pentateuch, Prophets, and some Writings is known as ‘Biblical Hebrew‘ or ‘Standard Biblical Hebrew‘.
(iii) Late Biblical Hebrew – Biblical Hebrew from after the Babylonian exile in 587 BC is known as ‘Late Biblical Hebrew.‘ Late Biblical Hebrew shows Aramaic influence in phonology, morphology, and lexicon, and this trend is also evident in the later-developed Tiberian vocalization system. For example, see the use of the conditional particle אִלּוּ replacing לוּ. Another difference between the two is the use of the relative pronoun אֲשֶר (introducing a restrictive clause, ‘that’) in the earlier period, being replaced with the clitic -שֶ in the later, both being used in Mishnaic Hebrew.
(iv) Qumran Hebrew – the Hebrew of the Qumran, attested in the Dead Sea Scrolls from ca. 200 BC to 70 AD, is a continuation of Late Biblical Hebrew.
For comprehensive resources on anything related to Classical Hebrew, see Biblical Hebrew.