On Tuesday, Mr. Trump, the presumptive Republican presidential nominee, who has lent his name in the past to several products, added a new item to the list: a $60 Bible. Mr. Trump posted a video on his social media platform in which he encouraged his supporters to buy the “God Bless the USA Bible,” named after the ballad by the country singer Lee Greenwood, which Mr. Trump plays as he takes the stage at his rallies.