Why not ask any religion or religious person why they need a Messiah? Christians commonly refer to Jesus of Nazareth as either the “Christ” or the “Messiah”
The English word Messiah is derived from the Greek term messias, which comes only twice in the New Testament (John 1:41; 4:25), when it is used to transliterate the Aramaic word mešîḥā’. To aid his Greek-speaking readers, John explains the meaning of messias by translating it as christos, the Greek term for “one who has been anointed.”