swear by

Idioms  

1. Have great reliance on or confidence in, as in She swears by her personal physician . [Early 1800s]

2. Also, swear to . Have reliable knowledge of, be sure of, as in I think she was going to the library but I can't swear to it . [Mid-1700s]

3. Take an oath by, as in I swear by all the saints in heaven . [Early 1200s]

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Example Sentences

Which is why I’ve come to swear by a three-part drinks strategy that feels both streamlined and generous: a little choreography that keeps everyone content without turning you into the household beverage director.

From Salon

All of these sports have their own history and methods; specific forms, procedures and even credos that those who take up the fight swear by.

From Salon

Tech moguls swear by it, Hollywood stars insist it keeps them trim.

From BBC

Lucy and Serena swear by them.

From BBC

So what about some of the other health targets that many of us swear by?

From BBC