The priestly blessing (birkat kohanim) is one of the most well-known passages in Jewish liturgy. 

According the Jewish oral law it is interpreted as a blessing for physical wellbeing and sustenance. 

The blessing, which is found in this week’s Torah portion, is divided into three levels, It is a blessing for physical wellbeing and sustenance. 

1: May the L‑rd bless you and watch over you.
2: May the L‑rd shine His countenance to you and favor you.
3: May the L‑rd raise His countenance toward you and grant you peace.

This blessing was always recited and spoken out loud by the priest as he lifted up his hands to form the name of God.

In so doing, the priest was able to put the name of God upon the congregation of Israel as in Numbers 6: 24-27.

When we study and practice the Torah (biblical commandments), we fulfill the mandate of creation. 

It is as if God allows us to be His partner. He creates, and we give His creation meaning and purpose by fulfilling his mitzvah.

The priestly blessing empowers us to make this three-step climb. 

In the first blessing, G‑d protects and sustains us. In the second, G‑d treats us as partners who have the power to work with Him on His project and give meaning to His creation. 

In the third stage, when we have reached the pinnacle of devotion and perfected our connection with God, we reach a state that transcends the universe completely and is completely at one with God.

(the level of being able to possess the spiritual capacity)

Article taken from Chabad.org