Where does “sifteth” come from?

sifteth (English) comes from English sift, from Middle English syften, from Old English siftan, from Proto-West Germanic siftijan — to sift.

Ancestry of “sifteth”, step by step

sifteth traces back through two separate lines of ancestry.

via English sift

StepLanguageWordMeaning
1EnglishsiftTo sieve or strain; To separate or scatter as if...
2Middle EnglishsyftenTo sift, strain, or percolate; to pass through a...
3Old Englishsiftanto sift
4Proto-West Germanicsiftijanto sift

via English eth

StepLanguageWordMeaning
1EnglishethA letter introduced into Old English to...
Every word from Proto-West Germanic siftijanEvery word from Old English siftanEvery word from Middle English syften