Bede the Venerable

Now the righteous man, according to the law, received the Child Jesus in his arms, that he might signify that the legal righteousness of works under the figure of the hands and arms was to be changed for the lowly indeed but saving grace of Gospel faith. The old man received the infant Christ, to convey thereby that this world, now worn out as it were with old age, should return to the childlike innocence of the Christian life.