swear by (something)

to strongly believe in something.

Though there's no scientific evidence for this method of finding water, some farmers swear by it.

Some teachers swear by stickers as a teaching tool and use them to teach kids everything.

• in the fast lane
• in the final analysis
• in the first place
• in the flesh
• in the fullness of time
• in the grand scheme of things
• in the great scheme of things
• in the grip of
• in the grip of something
• in the groove
• in the hands of
• in the hands of someone
• in the heat of
• in the heat of something
• in the heat of the moment
• in the hole
• in the hot seat
• in the house
• in the interim
• in their infinite wisdom
• in their wisdom
• in the know
• in the lap of luxury
• in the light of
• in the light of something