What is the…
Meaning: in the flesh
This was the act of grace whereby Christ took our human nature into union with his Divine Person and became man, the Second Adam. Christ is both God and man.
His Divine Person became united to human flesh (Acts 20:28; Romans 8:32; 1 Corinthians 2:8; Hebrews 2:11-14; 1 Timothy 3:16; Galatians 4:4, etc.).
The union is hypostatical, i.e., is personal. The two natures are not mixed or confounded, and the union is perpetual.