IN BRIEF
Jesus performed acts, such as pardoning sins, that manifested him to be the Saviour God himself (cf Jn 5:16-18). Certain Jews, who did not recognize God made man (cf Jn 1:14), saw in him only a man who made himself God (Jn 10:33), and judged him as a blasphemer.
Source: Catechism of the Catholic Church (Vatican.va)