In the account of the Book of Kings it says:
“And it was a handbreadth thick, and the brim thereof was wrought like the brim of a cup, with flowers of lilies: it contained two thousand baths.” (1 Kings 7:26)
It’s important to note that: 1 Kings Chapter 7 is a brief chapter about Solomon’s palace construction and everything inside and outside of it and this verse explains how were the cups, where priests used to wash in for uncleanliness, designed.
While, on the other hand, the record in the Book of Chronicles says:
“And the thickness of it was a handbreadth, and the brim of it like the work of the brim of a cup, with flowers of lilies; and it received and held three thousand baths.” (2 Chronicles 4:5)
There seems to be a “contradiction” here as the Book of Kings says that there were 2,000 baths while the Book of Chronicles says that there were 3,000 baths. What is the explanation of this discrepancy? Isn’t it evidence that the Bible has contradictions?
Not at all. The explanation, in fact, is quite simple and requires careful reading. The first verse says:
“…it contained two thousand baths…”. So the cup contained 2,000 baths.
The second verse, on the other hand, says:
“…and it received and held three thousand baths…” So the cup received 3,000 baths, as in, it has the capacity to receive 3,000 baths.
Taken together, these verses imply that the cup could receive 3,000 baths but only 2,000 baths were actually in it. So it was only two-thirds full. (see diagram)

In conclusion, the differences between the books of Kings and Chronicles are not “Bible contradictions” but merely more information for the reader to get the full story.