Could you clarify for me the difference between the Roman Centurion who asks Jesus once to heal his servant, and why we are told to pray unceasingly as the widow petitioned the judge? I believe that I only need to ask God once for something, then I can leave the matter with him. Am I taking the easy way out?
Your way certainly requires less effort, but it may not be the most productive. Here’s why.
The Centurion asked once and got an immediate answer (Matt. 8:5-7). The point of the Parable of the Persistent Widow was when we don’t get an immediate answer we should always pray and not give up (Luke 18:1-8). Therefore, if we get our answer immediately (like the Centurion) we stop praying for it, but if we don’t (like the widow) we should keep praying.
The Bible also tells us we must believe the Lord will answer our prayer when we pray (Matt. 21:22). Otherwise even constant prayer won’t get us anywhere (James 1:6-7).