A federal judge on Wednesday ruled to temporarily block a new law that would require Texas public schools to post the Ten Commandments in classrooms.

A district judge ruled Wednesday that Texas can’t require posters of the Ten Commandments to go up in certain school districts where parents have challenged the move.

“Even though the Ten Commandments would not be affirmatively taught, the captive audience of students likely would have questions, which teachers would feel compelled to answer. That is what they do,...