Genesis 12:8

Removed from thence unto a mountain, &c.— Either for better security from the inhabitants, or with a design of seeing more of the country. Here Abram built an altar (as it was usual on mountains); for, being fit places for contemplation, and, perhaps, by their height seeming to point the mind towards heaven above low earthly views, they were therefore chosen by pious men in ancient times, as altars of devotion raised by the Author of nature; and were approved of by God, till, like the sacred groves, they had been profaned by the impious rites of a barbarous superstition.