Samaritans were a mixed group of people, some the descendents of foreign colonists who had been placed in Samaria by the Assyrian and Babylonian leaders and some who were Israelite who had escaped captivity. They considered themselves Israelite and claimed Jacob as their father. The Jews disputed this. Samaritans felt they had a share in rebuilding the Jerusalem temple, but the Jews would not allow it. This angered the Samaritans, who then built their own temple in Mount Gerizim.
Samaritans had a version of the Pentateuch they considered law, but they rejected the Old Testament we have today, feeling it was disrespectful to them.
The Jewish people hated the Samaritans, considering them more unclean that other Gentiles. By the time of the Savior’s ministry, this hatred was intense. Even though the fastest way from Judea to Galilee was through Samaria, many Jews preferred to take the longer route around the city just to avoid the Samaritans.
Early in Jesus’ ministry, the Savior instructed the apostles not to teach in Samaritan towns yet, nor to any gentiles. At that time, the gospel was only to go to the lost sheep of Israel. However, in Luke 9, He did send apostles into Samaria to prepare the way for Him. This was when Jesus was going to Jerusalem because the time had come for Him to be delivered up. They rejected him because He was going to Jerusalem. Two of the apostles wanted to send fire to consume them as punishment, but Jesus stopped them, saying He saved men, not killed them.
Jesus sometimes addressed the issue of the feud between the Jews and the Samaritans through parables. He told of a man who was going from Jerusalem to Jericho and was attacked by thieves. A priest saw the severely injured man and crossed to the other side of the street to avoid him, as did a Levite. However, a Samaritan saw the man and tended his wounds. He then took the man to an inn and paid for his care. He instructed his followers to emulate that Samaritan, not the priest or the Levite. Jesus noted that when He healed ten lepers, only the Samarian thanked him.
Early in his ministry, Jesus stopped at a well. He was very tired and thirsty and asked the Samaritan woman he saw there for some water. She was amazed that he would speak to her, since He was Jewish and he was a Samaritan. He taught the doctrine of living water and also told her of her past. She understood then that He was a prophet and He identified Himself as the Christ. She went and told others, who came to hear Him. Many were converted because of her faith.
After Jesus’ resurrection, He instructed the disciples to be witnesses of Him in Samara. Phillip had much success teaching Samaritans.
Every Person in the New Testament by Lynn F. Price, Cedar Fort Publishing, 2002, United States of America
The Life and Teachings of Jesus and the Apostles