I have read several questions and answers on here regarding repeating words in prayer, but they do not answer why some common repetitions are allowable. Some examples: 1) During the Torah service, ...
The song "Tzur MiShelo", generally printed in Bentchers, Siddurim, Zimronim, etc., as a Friday night song, follows the pattern of Bentching (grace after meals), praising G-d and praying for ...
Some tunes for Lecha Dodi are conducive to repeating the chorus ("Lecha dodi ...") twice each time. I've noticed that some people, when using one of these tunes, repeat, while others avoid repeating ...