To provide respite from the seasonal state/church and religious onslaughts, Freethought Radio devotes most of its program to great secular songwriting. The very special guest is Lynn Lane, 86, widow of the legendary songwriter Burton Lane, who reminisces about her husband and lyricist Yip Harburg, both unbelievers, and creators of “Finian’s Rainbow,” now a hit Broadway revival. After a little news, the hosts dissect one of the show’s irreverent pieces, “The Begats,” play snippets of songs, and speak with the charming Lynn Lane.