Why is chicken considered kosher?!
Answers:
As far as Kashruth consideres birds it has to do with their feet. All birds that are not raptors are kosher. To tell if a bird is considered raptor, you look at it's feet. Moreover only birds that are within our tradition are kosher and the birds that are known in Jewish tradition are chicken, turkey, duck, goose, swan, doves and quails.
The kosher laws in regard to eating birds only list birds that are not to be eaten. Chicken is not listed as being prohibited..
Leviticus 11:13-19
Wherever you read that is wrong. Kosher is just a process that meets Jewish dietary law.
