The manger and Mount Calvary are separated only by the years it took to get from one to the other, for Christ’s mission concerned both places.
“Since therefore the children share in flesh and blood, he himself likewise partook of the same things, that through death…” (Heb 2:14)
God’s Son was born in order to die. His mission was not derailed by the cross. The Place of the Skull was not “plan B” after a failed attempt at securing earthly rule and renown. The incarnation happened for the purpose of crucifixion.
The cross was always the point because on that tree he died. And he could only die if he was human. God’s Son was born outside Jerusalem, and he’d die outside that city too.
His bloody birth was the way to his bloody death. But there’s power in this blood. In it sinners are washed white as snow.