12:1-6. God’s call to Abraham (the name he would give him instead of Abram: cf. 17:5) marks the start of a new stage in his dealings with mankind, because his covenant with Abraham will prove a blessing to all nations. It means that Abraham has to break earthly ties, ties with family and place, and put his trust entirely in God’s promise–an unknown country, many descendants (even though his wife is barren: cf. 11:30) and God’s constant protection. This divine calling also involves a break with the idolatrous cult followed by Abraham’s family in the city of Haran (apparently a moon cult) so as to worship the true God.
Abraham responds to God’s call; believing and trusting totally in the divine word, he leaves his country and heads for Canaan. Abraham’s attitude is in sharp contrast with the human pride described earlier in connection with the tower of Babel (cf. 11:1-9), and even more so with the disobedience of Adam and Eve which was the cause of mankind’s break with God.
The divine plan of salvation begins to operate by requiring man to make an act of obedience: in Abraham’s case, he is asked to set out on a journey. This plan will reach its ultimate goal with the perfect obedience shown by Jesus Christ “made obedient unto death, even death on a cross” (Phil 2:8), whereby all mankind will obtain the mercy of God (cf. Rom 5:19). Everyone who listens and obeys the voice of the Lord, all believers, can therefore be regarded as children of Abraham. “Thus Abraham ‘believed God, and it was reckoned to him as righteousness.’ So you see that it is men of faith who are the sons of Abraham. And the scripture foreseeing that God would justify the Gentiles by faith, preached the gospel beforehand to Abraham, saying, ‘In you shall all the nations be blessed.’ So then, those who are men of faith are blessed with Abraham who had faith” (Gal 3:6-9).
Jewish and Christian tradition sees the three things God requires Abram to give up as epitomizing the demands of faith: “Through these three departures–from country, kindred and father’s house,” according to Alcuin’s interpretation, “is meant that we have to leave behind the earthly man, the ties of our vices, and the world under the devil’s power” (“Interrogationes in Genesim”, 154).
Abraham’s response also involves an attitude of prayer, an intimate relationship with God. Although prayer makes its appearance at the very start of the Old Testament (cf. 4:4, 26; 5:24; etc.), it really comes into its own with our father Abraham, as the Catechism of the Catholic Church teaches: “When God calls him, Abraham goes forth ‘as the Lord had told him’ (Gen 12:4). Abraham’s heart is entirely submissive to the Word and so he obeys. Such attentiveness of the heart, whose decisions are made according to God’s will, is essential to prayer, while the words used count only in relation to it. Abraham’s prayer is expressed first by deeds: a man of silence, he constructs an altar to the Lord at each stage of his journey. Only later does Abraham’s first prayer in words appear: a veiled complaint reminding God of his promises which seem unfulfilled (cf. Gen 15:2-3). Thus one aspect of the drama of prayer appears from the beginning: the test of faith in the fidelity of God” (no. 2570).
Abraham gets as far as the central part of Palestine, from where he moves south, building as he goes altars to the Lord, to the true God, in places which will become important shrines in later periods. The biblical text shows that Yahweh accompanies Abraham and that the latter renders him acceptable worship, in contrast with the idolatrous cult practised by the inhabitants of the country (given the generic name of “Canaanites”). God, for his part, in all his appearances to the patriarch, promises to give this land to his descendants (cf. 13:15; 15:18; 17:8; 26:4). In this way the text is showing the radical source at the legitimacy of Israel’s possession of the land of Canaan. However, this promise of a land to the descendants of Abraham goes beyond the empirical fact of acquiring territory, and becomes a symbol of the blessings and the divine gifts in which all mankind will share.
Speaking about Abraham’s faith in the word of God, Paul interprets Abraham’s "descendant in the singular, as referring to one descendant only, Jesus Christ, because only he, being the Son of God and making himself obedient unto death, possesses all the divine goods and communicates them to man: “Christ redeemed us …] that in Christ Jesus the blessing of Abraham might come upon the Gentiles, that we might receive the promise of the Spirit. …] Now the promises were made to Abraham and to his offspring. It does not say, ‘And to offsprings,’ referring to many; but, referring to one, ‘And to your offspring,’ which is Christ” (Gal 3:13-16).
