Shirley Dobson told this story many years ago at a Women of Faith gathering in Minneapolis, Minnesota. This is how I remember it:

Shirley and her husband had been associated with a rural retreat center for many years. It was a breathtaking location with many wooded paths lacing through the hilly acreage. During one of their stays at the center, Shirley was struggling with a burden that was all consuming. She told us that she prayed about it constantly, but could not escape her worries. Eventually, she came upon on a plan: she decided to find a rock to represent her concerns then place it at the foot of a favorite tree along a trail at the center.  In that way, she said, she could physically surrender her anxiety to God and be free of it. Shirley did this and a sense of relief filled her.

Time passed. When Shirley was next at the retreat center the news was announced that the property had been sold, and the grounds would soon be closed. Shirley immediately thought of her “burden” rock at the base of the tree and ran quickly to the site to collect it. When she arrived at the spot,  she saw that the roots of the tree had grown over her rock. There was no possible way for her to take it back – to pick up her burden again. She had given it to God and he obviously intended to keep it.

Shirley explained how shocked and embarrassed she was when she saw the rock… and how thankful. She told us that she then realized a pattern in her life: she would give her burdens to God in prayer, but later take them back again, convinced that God was not up to the task of caring for her problems. Seeing the rock, her burden, embedded in the soil, surrounded by the roots of the tree taught her the truth of the matter – God is able and God is faithful.