What does this conflict about lay investiture indicate about medieval ideas of power, authority, and governance?

Pope Gregory was both devout and clever. ... The conflict between Henry IV and Gregory VII concerned the question of who got to appoint local church officials. Henry believed that, as king, he had the right to appoint the bishops of the German church. This was known as lay investiture.

Explanation:

the  seven  days  battles  were  a series of seven battles over seven  days from june 25 to july 1, 1862, near richmond, virginia,  during  the american civil war. the  seven  days ended with mcclellan's army in relative safety next to the james river, having suffered almost 16,000 casualtiesduring  the retreat.