But we tend also to hold onto other things much more trivial, such as our precious time. We don't have time for meditation in the morning, or whenever, because we have so much else to do and so little time. Abraham had only one little son, and had to take a long trip to a mountain for the sacrifice. I cannot even walk across my room to sit in a chair and sacrifice my time for God.
Time is what we have been given by God each day that we wake up. Some day, we won't have that time. It is God's gift to us, to be given back to God each day in prayer, and then in being helpful as the opportunity arises during the day. Trust and obedience are difficult virtues when it comes to a discipline of prayer.