Jamieson, Fausset and Brown on Titus 2:11

11. the grace of God--God's gratuitous favor in the scheme of redemption.

hath appeared--Greek, "hath been made to appear," or "shine forth" (Is 9:2; Lu 1:79). "hath been manifested" (Tit 3:4), after having been long hidden in the loving counsels of God (Col 1:26; 2Ti 1:9, 10). The image is illustrated in Ac 27:20. The grace of God hath now been embodied in Jesus, the brightness of the Father's glory," manifested as the "Sun of righteousness," "the Word made flesh." The Gospel dispensation is hence termed "the day" (1Th 5:5, 8; there is a double "appearing," that of "grace" here, that of "glory," Tit 2:13; compare Ro 13:12). Connect it not as English Version, but, "The grace ... that bringeth salvation to all men hath appeared," or "been manifested" (1Ti 2:4; 4:10). Hence God is called "our Saviour" (Tit 2:10). The very name Jesus means the same.

to all--of whom he enumerated the different classes (Tit 2:2-9): even to servants; to us Gentiles, once aliens from God. Hence arises our obligation to all men (Tit 3:2).