He...went to the hill east of Beit-El and pitched his tent...he built an altar there and called on the name of ADONAI (Genesis 12:8).
When God calls Abraham out of his homeland, he promises him land, offspring, and a blessing. Abraham arrives at Bethel in the heart of his new homeland, he responds to these promises by erecting two very different structures—a tent and an altar.
The tent is a symbol of transience. You don't really build a tent. When you reach your evening's destination, you pitch your tent; and when you leave, you pick up your tent; after you are gone, no sign remains.
In contrast, an altar is built to be solid and permanent. When Abraham returns to Bethel after his visit to Egypt, the tent is gone, but the altar remains. Abraham lives in the Land of Promise as a nomad, constantly moving, but the promise itself remains firm.
Outward circumstances may change, but the promises of God remain. As the tent reflects the impermanence of earthly things, so the altar represents the permanence of what is holy. A healthy spiritual life embraces both.
...maintain my original commitment to God, even though the circumstances of my earthly life may change.
RR