In promising, you limit options now, in order to have wonderful, fuller options later. You curb your freedom now, so that you can be free to be there in the future for people who trust you. When you make a promise to someone, both of you know that you are going to be there with and for them. “You have created a small sanctuary of trust within the jungle of unpredictability,” (Smedes)

Tim Keller, The Meaning of Marriage, p.93