The Second Commandment, the Regulative Principle, and Puritan Logic

How does one get from the second commandment to the Regulative Principle of Worship?  Here is the logic of Thomas Vincent in his exposition of the Shorter Catechism: 

 

God's forbidding the making of any graven image, and worshipping of it, doth clearly imply--

 

1.    That God must be worshipped by some means.

 

2.  That is a sin to worship God by graven images.

 

3.  That by consequence, it is a sin to worship God by means he hath not appointed in his word.

 

4.   That therefore it is a duty to worship God by the means which he has appointed, which being his ordinances, they must be received, observed, and kept pure and entire.