when i was in college, i went on a mission trip to mexico. and while i was there, i didn't have an alarm clock. so the first night i was there, i prayed "God, i know You made the universe and everything, so i know You're capable of waking me up in the morning. i need to be up at 7am. please wake me up. thank You!" and the next morning i woke up right on time.
i did that all week, and woke up right on time every morning. when i got back from the mission trip, i started to set my alarm, and it felt like God spoke to my heart and said "What? I can't wake you up now?" and i said, "well, You CAN... but..." and He said "trust Me." so i didn't set an alarm. the next day i woke up right on time.
for the next fifteen years, i never set an alarm. a couple amazing instances of this: when i was in college, i skipped classes quite a bit. and at my school, you had to go to class at least 75% of the time or you failed. well, i had skipped the maximum number of times in this one class. and the teacher of this class counted it as an absence if you were late. the class was at 9am. well, one morning i woke up at 9:10am on the morning of that class. i was like "God! You let me oversleep! now i'm gonna fail this class!" but at the same time i sensed He was doing something...
so i got up, put my shoes on, and ran to class. i walked in, and the class was all sitting there looking at me... but no professor. a few seconds after i walked in, the professor came in behind me, apologizing for being late. God knew he was going to be late, and He knew exactly how long it would take me to get up, put my shoes on, and get to class. and He woke me up at exactly the right time for all of that to happen. just so i could be telling you this story of His faithfulness right now.
another time, i was working at this camp, and this guy i barely knew asked me to wake him up at 7am the next morning. i didn't even have a watch! let alone an alarm clock. so i said "OK, God. You heard him. he needs to be up at 7..." and i went to sleep.
the next morning i woke up out of a dead sleep, and said to the guy over in his bunk, "hey man, it's time to wake up" and he said "oh, OK, thanks" and i said "BTW, what time is it?" and he looked at his watch and said "7am, straight up."