Meaning of the word "a stern chase is a long chase" in English

What does "a stern chase is a long chase" mean in English? Explore the meaning, pronunciation, and specific usage of this word with Lingoland.

a stern chase is a long chase

US /ə stɜrn tʃeɪs ɪz ə lɔŋ tʃeɪs/
UK /ə stɜːn tʃeɪs ɪz ə lɒŋ tʃeɪs/
"a stern chase is a long chase" picture

Idiom

a pursuit in which the pursuer is directly behind the pursued, often implying it will take a long time to catch up

Example:
We are gaining on them slowly, but a stern chase is a long chase.
The police knew that with the suspect's head start, a stern chase is a long chase.