McCreary, Religious Purpose, and Neutrality

Notice in McCreary Justice Souter talks about Lemon's requirement of "a secular legislative purpose," talks about a religious purpose as "an illegitimate purpose," and says the idea behind the Lemon test is to ensure "governmental neutrality between religion and religion, and between religion and nonreligion."

Hmmm. Let's think about the concept of neutrality between religion and nonreligion? Is calling a religious purpose "illegitimate" and mandating a predominant secular (i.e. a nonreligious) purpose,while forbidding a predominant religious purpose, neutral as between religion and nonreligion? Does the Lemon test as applied by Justice Souter violate itself by elevating the secular over the religious and thus flunking the requirement of neutrality "between religion and nonreligion?"

I am thoroughly confused?

Justice Thomas' "liberty" test seems so much more workable than a test that requires non-neutral neutrality between "illegitimate" religion and legitimate nonreligion. Under the liberty test, neither religious purposes nor secular purposes are classified as illegitimate. Both are legitimate and a matter for the democratic process. The EC is violated only when a State coerces or compels a person to participate in a religious activity. Both secular displays and religious displays are "legitimate" and the remedy for a person offended by either kind of passive public display is to takes a few steps to avoid it or turn his or her head to avert the eyes.

Which test is more neutral between religion and nonreligion? Souter's or Thomas'?