Be strong and courageous!
As a former Field Training Officer (FTO) in the Fire/EMS career, my responsibility was to
mentor new recruits. I was not only responsible to mentor the new recruit, but was also had to evaluate his/her abilities. I was there to help them with their transition from knowing how to do the job to actually doing it (didactic to practical). My knowledge and field experience provided assistance to help instill confidence in the recruit so he or she could go and work independently. This sometimes required me to step back to allow them the opportunity to practice their skills so I was not a crutch. I would have to push the recruit beyond his or her fears. Sure, they were never alone, but would have to rely on their abilities so to be available to respond to the call.
Many believers have a lot of head knowledge, but lack in the experience. Very few Christians are free from strongholds and in the field "doing" the word (James 1:21-22). But many fear the stepping out of the boat. Many lack trust in Christ or maybe trust of God's desire to work in and through them. They need mentors! Disciples available to lead them to become who they are designed to be in Christ, disciples.
As a former firefighter/paramedic, as an ER nurse and ministry leader, sure, there are times that I have been afraid. Running into a burning building when the roaches and rats are running out provided an opportunity to be afraid. In those moments I relied on the courage established first by knowing my call, having the knowledge , and my experiences either on the job or with my walk with Christ. I am confident that the one who called me is with me. Joshua 1:9 "Have I not commanded you? Be strong and courageous! Do not tremble or be dismayed, for the Lord your God is with you wherever you go." Knowing this, I can step out my front door into a filthy fallen world to do what God himself has called me to do.
Do you trust God's desire to work through you? Is your relationship with Him established in trust in Him or yourself? Have the heart desires of God become your heart desires? Are you beyond just the state of salvation living as a mature believer or still stuck drinking milk? Hebrews 5:13
Trust God! Have courage! Respond to the call!