It would help to know which three crises you're referring to.
The Black Death was one, the relocation of the papacy to Avignon for 70 years was another, but which is the third?
The relocation of the papacy from Rome to Avignon (which is in France) weakened the power of the Pope because there were, at one time, at least three men claiming the office, and during the nearly three quarters of a century that the "exile" lasted, there were often at least two claimants to the papal throne: one in Rome and the other in Avignon.
You can plainly see how having multiple claimants to the office would lead to a serious erosion of trust in the institution of the Catholic Church in Europe, just as it would cause civil unrest in a secular kingdom, with factions supporting one against the other.
The Black Death brought about the death of millions of people, and in its wake left few workers not only in Europe but all over the known world. In Europe, however, those who survived the pandemic began to realize that, if they were laborers, they had suddenly become a very hot commodity and could negotiate better pay for themselves and, in some cases, better living conditions for their families (if they had any left).
The deaths of so many also allowed the survivors to acquire more land and establish themselves as forces to be reckoned with not only by their fellow farmers, but by their landlords as well.
Since even a humble day laborer could ask (and often receive) higher wages than he could before the plague, it led to a lot of unrest. Those who had previously worked the land primarily for the benefit of an overlord as tenant farmers were now in a position to negotiate new rules and sometimes succeed in buying land for themselves.
This led to social unrest and was perceived by those who had traditionally held power as a major threat to stability. The people they had employed to work their land were asking higher wages and the fact that they could get them elsewhere put landholders in a position of choosing to agree to the workers' demands or losing their services.
This was also true in the towns, where apprentices were demanding better working conditions and employees higher pay, so you can see nothing happened in a vacuum.
This, of course was seen as a threat by the nobles who owned the land; they must either give in to the tenants' calls for wages and reorganization of traditional services and fees or tend the land themselves--something unthinkable to the knightly class.
As to the third crisis, I can't think of what it might have been.