Q. After Jesus was anointed and filled by the Holy Spirit he was led into the wilderness, fasted 40 days and was tempted by Satan. If you have a study on why this had to happen in this way could you direct me to it please. And was Jesus tempted before he was filled by the Holy Spirit for his ministry on earth?
A. As you said, Jesus was formally tempted after being filled with the Holy Spirit. I believe one reason it had to happen this way was for him to demonstrate the proper method for resisting temptation. The devil would bring different temptations to us than he did to Jesus, but like His, our temptations are tailored to suit our particular desires. He was hungry after fasting for 40 days, He wanted to be sure that His Father would protect Him on His dangerous assignment, and He was sent in part to regain ownership of all the Kingdoms of the world. In each case Jesus responded with Scripture instead of trying to engage him in dialog (like Eve did for instance) and used them to reinforce His trust in God.
There’s no mention of a temptation before hand although he was a man in the world for 30 years before his ministry began and would have been exposed to the temptations normal to the time. Hebrews 5:15 says he was tempted in every way yet was without sin.