Continuing our Advent look at Messianic prophecies for this year, which we began in Advent 2011 and continued in 2102 and 2013, the earlier posts of the series may be read here, here, here ,here, here, here, here, here , here , here, here, here, here , here and here we come to Jeremiah 23: 5-6:
 Behold the days
come, saith the Lord, and I will raise up to David a just branch: and a king shall reign, and shall be wise, and shall execute judgement and justice in the earth.
 In those days shall Juda be saved, and Israel shall dwell confidently: and this is the name that they shall call him: the Lord our just one.
Pope Leo in Sermon 28, his great Christmas sermon, illuminates this passage for us:
But the majesty of the Son of God in which He is equal with the Father in its garb of a slave’s humility feared no diminution, required no augmentation: and the very effect of His mercy which He expended on the restitution of man, He was able to bring about solely by the power of His Godhead; so as to rescue the creature that was made in the image of God from the yoke of his cruel oppressor. But because the devil had not shown himself so violent in his attack on the first man as to bring him over to his side without the consent of His free will, man’s voluntary sin and hostile desires had to be destroyed in such wise that the standard of justice should not stand in the way of the gift of Grace. And therefore in the general ruin of the entire human race there was but one remedy in the secret of the Divine plan which could succour the fallen, and that was that one of the sons of Adam should be born free and innocent of original transgression, to prevail for the rest both by His example and His merits. Still further, because this was not permitted by natural generation, and because there could be no offspring from our faulty stock without seed, of which the Scripture says,
Who can make a clean thing conceived of an unclean seed? Is it not You who is alone Job 14:4? David’s Lord was made David’s Son, and from the fruit of the promised branch sprang One without fault, the twofold nature joining together into one Person, that by one and the same conception and birth might spring our Lord Jesus Christ, in Whom was present both true Godhead for the performance of mighty works and true Manhood for the endurance of sufferings.