A child stands atop Isaiah’s peaceable kingdom in Tuesday’s first reading at Mass:

“The calf and the young lion shall browse together, with a little child to guide them. A shoot shall sprout from the stump of Jesse, and from his roots a bud shall blossom.” (Isaiah 11,1)

It takes a child to believe the astounding promises Isaiah makes. Adults, hardened by the experience of life, struggle with the prophet’s words. That’s why Advent invites us to become children, not physically, of course, but spiritually.

Become like little children. That’s what Jesus told his followers,  and he praised the childlike:

“I give you praise, Father, Lord of heaven and earth, for although you have hidden these things from the wise and the learned, you have revealed them to the childlike.” Luke 10

Only the childlike believe in great promises.

What does being “childlike” mean? Here’s what St. Leo the Great said about Jesus’s teaching on spiritual childhood: To be a child means to be “free from crippling anxiety, to be forgetful of injuries, to be sociable and to keep wondering at all things.”

A little child in its mother’s arms has no worries. It’s a good place to be, free from anxieties and a mother’s voice promising all will be well. Advent brings that grace back  to us; a grace we can lose so easily.

Jesus experienced that grace in Mary’s arms. Herod’s soldiers, like Isaiah’s Assyrian armies, were on their way. It’s a poor place where he’s born, no room in the inn, but the Child in his mother’s arms has no fear. All will be well.

Injuries would come. The world can turn hostile. The promises may seem far away, but from infancy to his death, Jesus knew he was a child of God, his Father, in God’s caring hands and destined for God’s kingdom.