The phrase "year of grace" is a noun that refers to any year in the Christian calendar. It is often used to denote the time that has passed since the birth of Jesus Christ, which is the starting point for the Christian calendar, also known as Anno Domini (AD).
In more complex discussions, "year of grace" can imply a time of mercy or favor, especially in a religious context. It can also be used to describe a period of spiritual renewal or significance.
Apart from its literal meaning, "year of grace" can also carry a connotation of a period during which people are offered forgiveness or a chance to improve their lives spiritually.
There are no direct idioms or phrasal verbs that include "year of grace," but in religious discussions, you may encounter phrases like "in the grace of God," which refers to being favored or blessed by God.
In summary, "year of grace" is a term used mainly in Christian contexts to refer to years counted from the birth of Jesus.