Like 2008’s Noah’s Arc: Jumping the Broom, in which two boyfriends wed on Martha’s Vineyard, Salim Akil’s first feature finds inspiration in the 19th-century marriage custom, and also takes place on the affluent island. But this Jumping the Broom is an exclusively hetero affair, with extra holiness provided by producer and mega-church pastor T.D. Jakes, who has a small role as a reverend. Well-heeled Sabrina (Paula Patton) makes a promise to God that she’ll give up one-night stands and won’t spread her legs again until she and her fiancé, Jason (Laz Alonso), a striver with blue-collar origins, have tied the knot. Akil, who directed several episodes of Girlfriends, one of the smartest TV shows about race, has less to work with in Elizabeth Hunter and Arlene Gibbs’s script, a wan attempt to mine class clash for both jokes and teachable moments. Overseeing the wedding is Sabrina’s sadiddy mother, Claudine (Angela Bassett), unable to conceal her disdain for Jason’s USPS-employee mother (Loretta Devine) and his loutish relatives. The battle of wills between the matriarchs at least provides two fine actresses, too often in projects not worthy of them, with the opportunity to work opposite an equal. But a late-act crisis precipitated by scandalous maternity news is straight out of the Tyler Perry Academy of Plotting, and all the beseeching of the Lord sounds like little more than product placement.