The God of this people of Israel chose our fathers
Abraham, Isaac, and Jacob, and their seed after them, to be a peculiar people to himself; wherefore he is often, as here, styled their God, and whom he distinguished and blessed with many blessings, civil and religious, above all people upon the face of the earth. The apostle seems particularly to address himself to the Gentiles, the inhabitants of Antioch, and the proselytes of righteousness, now in the synagogue, ( Acts 13:42 Acts 13:43 ) and, as it were, with his finger pointed to the native Jews present, the descendants of Abraham, Isaac, and Jacob, a part of the people whose God the Lord was:
and exalted the people when they dwelt as strangers in the land of
Egypt
as they did for many years, and as the Lord foretold to Abraham they should, ( Genesis 15:13 ) This refers either to the great honour and dignity Joseph was advanced unto, and to the favours and privileges bestowed on Jacob and his family at the first of their sojourning in that land; or to the great increase of their posterity towards the close of it, even when they were the most oppressed and afflicted.
And with an high arm he brought them out of it
out of the land of Egypt, and out of their oppression in it; which was owing to, and was a wonderful display of his mighty power and great strength here expressed by an "high arm" for nothing short of that could have wrought deliverance for them.