Institutes of the Christian Religion (1559) - John Calvin
Book 2 - God the Redeemer
Chapter 8 - Explanation of the Moral Law:
The 10 Commandments
Section 11-12 - The two Tables of the Law
The first table deals with ho we are to worship Him.
The second table deals with how we are to act toward others.
Jesus confirms this in His summary of the Law - Matt 22:37-39.
It is vanity to try to be righteous among men (second table of the law)
without right worship of God (first table).
Section 12 - The distribution of the commandments in the two Tables
Some say the commandment against images (2nd) is counted under the 1st,
and that the 10th against coveting is really 2. So the first 3 commands are the first table, and the last 7 are the 2nd table, by this count.
But the first table is the 1st four commandments; the second is the last 6.
This is so partly because Jesus includes the fifth commandment in the second table - Matt 19:19.