Toomey on Church and State

There has been a lot in the news today about a Delaware senate candidate's comments on the separation of church and state. Pat Toomey, running for Senate in Pennsylvania, wrote something similar in his book, The Road to Prosperity. From page 170:

The best way to address this argument [school vouchers used at religious schools] is to take a look at the Constitution itself. The relevant portion of the First Amendment reads: "Congress shall make no law respecting an establishment of religion, or prohibiting the free exercise thereof." The text of the Constitution is pretty clear about what is prohibited -- an establishment of religion. constitutional scholars have argued for years over the subtleties of the Establishment Clause, as it is know, but how exactly does giving money to parents to chose their children's schools constitute "an establishment of religion?"

Proponents of the constitutional argument often refer to Jefferson's famous line regarding a "wall of separation between church and state." They neglect to mention that this metaphorical line was written in an 1802 letter an doesn't appear in the Constitution at all.