Namesake

google

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mid 17th century: from the phrase for the name's sake .

wiktionary

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Mid-17th century. From name +‎ sake. From the phrase "for (one's) name's sake", first found in Bible translations as a rendering of a Hebrew idiom meaning "to protect one's reputation" or possibly "vouched for by one's reputation." A familiar example is in Psalm 23:3, "he leadeth me in the paths of righteousness for his name's sake" (King James Bible, 1604).

etymonline

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namesake (n.)

"person named for the sake of someone, one who has the same name as another," 1640s, probably originally (for the) name's sake. See name (n.) + sake (n.1).