John Calvin Commentary Genesis 28:19

"And he called the name of that place Beth-el. But the name of the city was Luz at the first." — Genesis 28:19 (ASV)

And he called the name of that place Beth-el. It may appear absurd that Moses should speak of that place as a city, concerning which he had said a little while before that Jacob had slept there in the open air. For why did he not seek lodging, or hide himself in some corner of a house?

But the difficulty is easily solved: the city was not yet built, nor did the place immediately take the name Jacob had assigned it, but lay hidden for a long time. Even when a town was later built on the spot, no mention was made of Beth-el, as if Jacob had never passed that way. The inhabitants did not know what had happened there and so, according to their own imagination, they called the city Luz. This name it retained until the Israelites, having taken possession of the land, recalled the former name, which had been abolished, into common use, as by an act of restoration.

It should also be noted that when their descendants, in foolish emulation, worshipped God in Beth-el—since this was done without a divine command—the prophets severely denounced that worship, calling the place Bethaven, that is, "the house of iniquity."

From this we infer how unsafe it is to rely on the examples of the fathers without the word of God. Therefore, the greatest care must be taken concerning the worship of God, ensuring that what men have once done is not taken as a precedent. Instead, what God himself has prescribed in his word must remain an inflexible rule.