Before Samson was born, God sanctified and dedicated him. That means God set him apart. Samson was set apart because God wanted to use him to save his people from the Philistines. Samson was called a Nazarite. Two things Nazarites never did, was to drink juice made from grapes or cut their hair. God told Samson's mother that if his hair was ever cut, he would lose his great strength.
As part of being set apart, Samson was only supposed to choose a Jewish girl to be his wife. The problem is that Samson loved Philistine girls. One of the Philistine girls he fell in love with was named Delilah. She tricked him into telling her the secret of his great strength, then she cut off his hair and let the Philistines capture him. They poked out Samson's eyes and then made him turn the grinding mill like an animal. Because Samson would not follow God's commands, he was no longer sanctified. Because of this he lost his eyes and his dignity. When we give our self to Jesus, He sets us apart from sin, so we are sanctified. From then on we are to live as a new creature (or person) who is sanctified. That means that as we live by God’s Word we are separated and protected from sin.
(ref. Judges 16 )