ISB ~ Matthew 1 v1
book of the genealogy:A title for the following ancestry (1:2-16) and the entire Gospel. The opening words recall the Greek OT in Gen 2:4 and 5:1.
Christ:A title (Gk. Christos) meaning the “Anointed One”. It is the Greek rendering of the OT word for “Messiah”. According to Lk 4:18-19, Jesus is anointed by the Holy Spirit (cf. Acts 10:36-38). It is this title for Jesus that Matthew elucidates throughout his Gospel.
See word study:Christ at Mk 14 (CCC 436).