For one thing, it predicates on Herod, not the infant Jesus. When the Three Kings told Herod of their discovery, Herod assumed that Jesus must have been some kind of subversion, a "new born King" who threatened Herod's worldly domain. That's how megalomaniac dictators think. Roth brought out the macabre in the Nocturnal March passages. Shades of Symphonie fantastique haunt Herod's nightmares. Christopher Purves sang Herod's arias with grim force. The first part of the oratorio is so vivid, that the angel's warning comes almost as an afterthought. The Holy Family make a dash for it escaping the bloodbath that will fall on all other baby boys (not necessarily newborns).
For the moment, however, Berlioz sticks to Bethlehem. The choral singing in the Shepherd's Farewell is suitably reverent, but the music in the overture to the Flight Into Egypt sparkled with inventive images. Do the rising figures suggest the endless skies above the stable ? No simple "star motifs". Yann Beuron sang the famous "Le repos de la Sainte Famille" with clarity so we could hear the swaying line: the rocking of a cradle, or a presentiment of the dangerous journey to come ? His "Alleluia!" rang out firmly, echoed by the young choristers from on high, like angels.
The Holy Family are refugees but L'arrivé à Saïs is fraught.The natives don't like immigrants, but one family offers shelter. Perhaps Berlioz was drawn to this aspect of the story because he, too, was an outsider, and knew that there were alternatives to the circles he lived in. But more likely he enjoyed the opportunity to contrast vaguely medieval a cappella with exotic, "Arabic" forms. The Trio was exqusiite, the flutes dancing solemnly with the harp, just alien enough to suggest something quite beyond the experiences the Sainte Famille would have known. Beuron sang the Epilogue with the right mix of fragility and affirmation. Jesus will stay with carpenters, under cover, but one day he will come into his own, eclipsing Herod, Nazareth and indeed the world as Christians know it.
L'enfance du Christ is described as a "meditation" but not in the sense of Messaien's Vingt Regards du l'Enfant Jésus (read more here). Messian contemplates a religious mystery. Berlioz gives us good music, which we can take at face value if we wish, but get much more out of if we know what he's into.