Some mornings when I go online, Facebook shows me “memories”—things I’ve posted on that day in previous years. These memories, such as photos from my brother’s wedding or a video of my daughter playing with my grandmother, usually make me smile. But sometimes they have a more profound emotional effect. When I see a note about a visit to my brother-in-law during his chemotherapy or a picture of the staples across my mother’s scalp after her brain surgery three years ago, I am reminded of God’s faithful presence during difficult circumstances. These Facebook memories nudge me towards prayer and gratitude.

All of us are prone to forget the things God has done for us. We need reminders. When Joshua led God’s people towards their new home, they had to cross the Jordan River (Joshua 3:15–16). God parted the waters, and His people walked through on dry land (v. 17). To create a memorial of this miracle, they took twelve stones from the middle of the riverbed and stacked them on the other side (4:3, 6–7). When others asked what the stones meant, God’s people would tell the story of what God had done that day.

Physical reminders of God’s faithfulness in the past can remind us to trust Him in the present—and with the future.