He has performed mighty deeds with His arm; He has scattered those who are proud in the thoughts of their hearts.
51. He hath done might This means, “he hath wrought powerfully.” The arm of God is contrasted with every other aid: as in Isaiah, “I looked, and there was none to help,” (Isaiah 63:5;) “therefore,” says he elsewhere, “his arm brought salvation unto him; and his righteousness, it sustained him,” (Isaiah 59:16.) Mary therefore means: God rested satisfied with his own power, employed no companions...
We have here an interview between the two happy mothers, Elisabeth and Mary: the angel, by intimating to Mary the favour bestowed on her cousin Elisabeth (Luk 1:36), gave occasion for it; and sometimes it may prove a better piece of service that we think to bring good people together, to compare notes. Here is, I. The visit which Mary made to Elisabeth.
Commenting on Luke 1:39-56
He hath showed strength with his arm,.... Of almighty power, in the business of the incarnation, and in working out salvation for his people; which is done by his own arm, he being mighty to save, and travelling in the greatness of his strength; see Isa 63:1.