Luke now presents a sign of the birth. As with the other angelic announcements in this infancy section (1:19–20, 36), a sign comes with the announcement (Fitzmyer 1981: 410). The sign’s unusual character, the baby in a feed trough, confirms the announcement’s truth. The expression this will be a sign has OT roots (Exod. 3:12; 1 Sam. 2:34; 14:10; Isa. 37:30; 38:7; Rengstorf, TDNT 7:231 n. 213). The shepherds are to look for a newly born child lying in a feed trough (2:7).13 Βρέφος (brephos)
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