As a practical matter, leaving her jar meant the Samaritan woman could accelerate her return to the city in order to get the Good News to her people faster. Certainly this would be a blessing to them all. She teaches us an important lesson here: Those tasked with spreading the Gospel must not burden themselves with anything that will hinder them.
Here is another example of leaving behind the old life and what we trusted in, to follow Jesus.
Mat 4:18 And Jesus, walking by the sea of Galilee, saw two brethren, Simon called Peter, and Andrew his brother, casting a net into the sea: for they were fishers.
Mat 4:19 And he saith unto them, Follow me, and I will make you fishers of men.
Mat 4:20 And they straightway left their nets, and followed him.
Not always do we leave everything behind, in keeping with the starting example of the woman at the well, we leave behind that which hinders. Sometimes we keep the things we are familiar with to serve the Lord. An example is Moses who was called to deliver Israel from bondage in Egypt. Moses had been a shepherd for forty years. He used the tool of the shephard, a rod, to bring God glory. Exo 4:2 And the LORD said unto him, What is that in thine hand? And he said, A rod.
Exo 4:3 And he said, Cast it on the ground. And he cast it on the ground, and it became a serpent; and Moses fled from before it.
Exo 4:4 And the LORD said unto Moses, Put forth thine hand, and take it by the tail. And he put forth his hand, and caught it, and it became a rod in his hand:
Exo 4:5 That they may believe that the LORD God of their fathers, the God of Abraham, the God of Isaac, and the God of Jacob, hath appeared unto thee.
God used that rod to perform miracles in Egypt. The thing to see is the Lord may use the tools we are skilled to use, for his glory. A musician, plays music for the Lord. An artist makes art for the glory of the Lord. What ever we have the Lord will use for his glory. Sometimes we are to put all aside. I see this as to rely on the Lord as he leads, it may be to leave behind a trade or profession. It couldbe to use the trade or profession for his glory.