Young Earth Creationists are claiming that the word Yom is Singular when referring to "a day" (24 hour period) and plural when referring to time longer than a 24 hour period. This is their attempt to prove that the earth is 6,000 years old. Is this correct? Can you please provide some insight into this as it is causing a great deal of disagreement. G-d bless.
I'm not familiar with their claims, but can just say that the word Yom is literally 24 hours, and "yamim" is plural of yom, but there are many (!) exceptions (see Breishit 7, 4 where both are used; Shmot 24, 18; Bamidbar 13, 25; Dvarim 9, 9 and many more) where "yom" is used for plural, or many days. That being said, it's important to stress that the Torah is not a history book, nor a science manual, but a guide for Godly living. Accordingly, when such information, as in creation, is purposely vague, that’s the real answer: we don’t really care how long the days were. If a certain generation has reason to think that the theory of evolution is true, and that creation took millions of years, we can fit that into the Torah, and if science ever thinks that it can prove otherwise, we’ll be able to fit that into the text, as well, for what science believes in every generation, is beneficial for that generation. The Talmud teaches us that the real meaning of the story of creation can only be taught to individual selected students (Chagiga 11b), because it’s not (!) simple and cannot be taken at face value. For example, some cite in this context the verse: “for 1,000 years is in Your eyes is like one day…” (T’hilim 90,4). The term “yom” or day throughout the Tanach refers sometimes to the 24 hour unit (called in the Talmud (Brachot 3a) and in modern Hebrew: y’mama, from the same root as “yom”), and sometimes just to the light half (as opposed to the night), as is clear from both usages of the term in the first verse in the Torah. Nevertheless, in the creation, it may be otherwise, for the sun and moon were only created on the 4th day, so most probably, it's meant to be understood differently, on the first day. Many of the classic commentaries deal with this issue here, I suggest Rabbi Samson Raphael Hirsch and the Malbim who often deal with the literal meaning of the word and its usage throughout Tanach. With Love of Israel, Rav Ari Shvat