When the Lord gives you a command, He certainly sees you straining to be faithfully obedient to His command. If this is where you are at, it will be a comfort for you to know that He desires to encourage you to continue to be obedient so you can complete His command!
Oftentimes, when the Lord uses our lives, the cycle we go through in ministry is first a test, then a rest. If we never learn this cycle, it seems to always lead to ministry burnout.
In learning how to serve God, ministry is caught more than taught. As a disciple sees and experiences the ministry, later on, God willing, the disciple will mimic the ministry.