John Calvin Commentary Genesis 12:4

"So Abram went, as Jehovah had spoken unto him; and Lot went with him: and Abram was seventy and five years old when he departed out of Haran." — Genesis 12:4 (ASV)

So Abram departed. Those who suppose that God was now speaking to Abram in Charran use these words in support of their error. But the objection is easily refuted; for after Moses has mentioned the cause of their departure, namely, that Abram had been compelled by God's command to leave his native land, he now returns to the main narrative.

We do not know why Abram remained in Charran for a time, except that God intervened to prevent him from immediately seeing the land, which, although still unknown, he had nonetheless preferred to his own country. He is now said to have departed from Charran so that he might complete the journey he had begun. The next verse also confirms this, stating that he took Sarai his wife and Lot his nephew with him.

Just as under the leadership and guidance of his father Terah, they had departed from Chaldea, so now that Abram has become the head of the family, he continues and completes what his father had begun. It is still possible that the Lord again urged him to proceed, after his father's death, and that He confirmed His former call with a second oracle.

However, it is certain that here the obedience of faith is commended, not merely as a single act, but as a constant and continuous way of life. For I do not doubt that Moses intended to say that Abram remained in Charran, not because he regretted his decision, as if he were inclined to deviate from the direct path of his calling, but because he kept God's command always fixed in his mind.

Therefore, I would rather connect the clause, As the Lord had spoken to him, to the first oracle, meaning that Moses would be saying, ‘He stood firmly in his purpose, and his desire to obey God was not broken by his father's death.’ Moreover, we have here, in essence, a rule prescribed for us for the regulation of our whole life: to attempt nothing except by divine authority.

For, however people may dispute concerning virtues and duties, no work is worthy of praise, or deserves to be counted among virtues, unless it is pleasing to God. And He Himself testifies that He regards obedience more highly than sacrifice (1 Samuel 15:22). Therefore, our life will be rightly ordered when we depend on the Word of God and undertake nothing except at His command.

And it should be observed that the issue here is not about one particular work, but about the general principle of living piously and uprightly. For the subject under consideration is Abram's calling, which is a common pattern for the life of all the faithful.

Indeed, we are not all commanded indiscriminately to leave our country; this aspect, I grant, is specific to Abram. But generally, it is God’s will that all should be in submission to His Word and should seek the law for the regulation of their lives from His mouth, so that they are not carried away by their own will or by human opinions. Therefore, by Abram's example, complete self-renunciation is prescribed, so that we may live and die to God alone.