I remember being blown away the first time I read this verse:
“I [Joshua] was forty years old when Moses the servant of the Lord sent me from Kadesh-barnea to spy out the land, and I brought him word again as it was in my heart.” Joshua 14:7 ESV
I was blown away because this meant Joshua was 80 years old when he started leading the Israelites. As you recall, the Israelites spent forty years wandering in the wilderness after they refused to enter the promised land, and Joshua died at the age of 110 (Joshua 24:29). This means he spent only 30 of his 110 years of life actually leading.
We are trying to raise a generation of revolutionaries, young leaders to seize opportunities for God. I think we have great potential for equipping them with tools no other generation has had. However, every leader who is called to a Joshua Leadership can expect a time of preparing and waiting, sometimes a lengthy one. For our own sakes, God does not give us more than we can handle, and the bigger the task, the bigger the waiting.
Further, as a Joshua Leader, you may need to wait on the people God is calling you to lead. Joshua had to spend those 40 years in the wilderness because of other people’s unbelief. I wonder what went on in Joshua’s mind during that time. It could easily have seemed like a detour, and he could easily have become bitter towards the Israelites for their unbelief. However, I can recall no indication in Scripture of such a response.
What does this mean practically?
If you find yourself “stuck” by someone else’s unbelief, know that God’s promises for your life are greater than anyone elses’s action. Resolve in your heart to keep walking with God, believe His promises, and not let yourself become bitter.
If you find yourself in a time of preparation, enjoy it! God is transforming you into the man or woman He has called you to become, and that’s a beautiful thing! If it seems slow, it may be your own stubbornness, or it just might be that God has great things in store, and He’s waiting to take you there until you are thoroughly equipped to handle the task He has prepared for you.
Remember, the bigger the task, the bigger the preparation, the bigger the wait.
All for Christ.
Unveiled Glory 
You said-“If you find yourself in a time of preparation, enjoy it! God is transforming…” A hearty Amen to that comment! Sometimes we get so focused on finding our gift/calling/sweet spot that we chafe at the preparation time needed for growing us into more well rounded people of purpose. It is interesting to reflect on Jesus life from age 12 to 30…apparently preparation time for the Christ…a time that would be considered mundane by many of us. Imagine the King of Kings “wasting” time by working with His hands on carpentry projects. In reality, no waste of time there.
Blessings