And a woman who had been suffering from a hemorrhage for twelve years, came up behind Him and touched the fringe of His cloak; for she was saying to herself, "If I only touch His garment, I will get well." But Jesus turning and seeing her said, "Daughter, take courage; your faith has made you well." At once the woman was made well. [Matthew 9:20-22 NASB]The book of Mark gives more details of this incident.
"A woman who had had a hemorrhage for twelve years, and had endured much at the hands of many physicians, and had spent all that she had and was not helped at all, but rather had grown worse— after hearing about Jesus, she came up in the crowd behind Him and touched His cloak. For she thought, “If I just touch His garments, I will get well.” Immediately the flow of her blood was dried up; and she felt in her body that she was healed of her affliction. Immediately Jesus, perceiving in Himself that the power proceeding from Him had gone forth, turned around in the crowd and said, “Who touched My garments?” And His disciples said to Him, “You see the crowd pressing in on You, and You say, ‘Who touched Me?’” And He looked around to see the woman who had done this. But the woman fearing and trembling, aware of what had happened to her, came and fell down before Him and told Him the whole truth. And He said to her, “Daughter, your faith has made you well; go in peace and be healed of your affliction.”" [Mark 5:25-34 NASB]
This woman was afraid. It wasn't that she was shy or timid, but she had a legitimate reason to be afraid. In the Jewish culture, any person with an issue of blood was considered unclean, and anyone they touched became unclean as well. It was her obligation to keep herself away from other people. Her unhealed hemorrhage gave her the same status as a leper.
Jesus had previously healed a leper by walking up to the leper and touching him. This case is different. Jesus didn't approach her. She didn't get his attention and ask to be healed. She tried to be secretive, by blending into the crowd, and brushing against him, as so many others were. Jesus was not fooled. He was aware of the difference between a casual touch, and the touch of faith.
I'm only speculating, but I think that when Jesus said, "Who touched My garments?", he already knew the answer. The Bible says, "He looked around to see the woman who had done this." He knew where to look. I think His purpose was to give her the opportunity to publicly testify.
Jesus said, "Therefore everyone who confesses Me before men, I will also confess him before My Father who is in heaven. “But whoever denies Me before men, I will also deny him before My Father who is in heaven." [Matthew 10:32-33 NASB]
Jesus gave this woman the opportunity to either confess Him or deny Him. In spite of her fear and trembling, she chose wisely and confessed Him.
She was healed the moment she acted in faith. The power of God flowed from Jesus the moment she touched Him. His words to her weren't for her healing, but for her comfort.
He called her "Daughter". She is the only one recorded in the Bible to be called "Daughter". Her flow of blood meant that she had been unclean, ostracized, and outcast for the last 12 years. Jesus' term of endearment demonstrated complete acceptance.
Jesus said, "go in peace and be healed of your affliction." She had already been healed, but now, instead of sneaking away, she can go with Jesus' blessing.