The second son slept with Tamar, but didn’t like the idea of producing a child for his brother. So at the last moment during sex, he withdrew so she couldn’t get pregnant. This made the Lord angry and he killed the second son.   
Judah then told Tamar, “Go back and live as a widow in your father’s house. I’ll give you my youngest son when he grows up.” So she did as she was told. 
Years went by and yet Judah didn’t give Tamar his youngest son. He was worried that his last son would die like his brothers. Still, she could see that the youngest was now old enough to marry. 
About that same time, Judah’s wife died. Afterwards, he and his friend traveled to a place to shear sheep. Someone told this to Tamar. She immediately changed her clothes, so she wouldn’t look like a widow. She then covered her face with a veil. 
She went and sat down next to the road, where her father-in-law would travel that day. He saw her and assumed she was a prostitute because she wore a veil over her face. He didn’t know she was his daughter-in-law. 
He said to her, “Let me sleep with you.” “What will you give me?”
He said, “When I get to my flock, I’ll send you a young goat.”
 She said, “I’ll have sex with you, but you must leave something with me so I can be sure you’ll send me the young goat.” 
“What do you want?” 
She said, “I want your walking stick and the ring you keep on the cord around your neck.” 
He gave these things to her, and then had sex with her, and she became pregnant. 
After they were done, she went home, removed her veil, and once again put on her widow’s clothes. 
Once Judah got to his flock, he asked a friend to take the young goat back to the prostitute. He said, “Be sure to get the things I left with her.” 
When the friend got there, he couldn’t find her. He asked some men who lived in that area, “Where is the prostitute that sits by this road?” 
They said, “There has never been a prostitute sitting by this road.” 
The friend went back and told all of this to Judah. He laughed, “Then let her keep those things I gave her. I tried to fulfill my part of the bargain.” 
Three months later, someone told Judah, “Your daughter-in-law acted like a prostitute and now she’s pregnant.” 
Judah was furious. He yelled, “Bring her here! We’ll burn her.” 
As they were getting her, she sent a message to her father-in-law. It said, “I can identify the man who got me pregnant. These things belong to him. Do you recognize them?” 
As soon as he saw his ring and walking stick, he knew what had happened. He said, “She’s a better person than me. I promised to give her my youngest son, but didn’t do it.” He never went to bed with her again. 
She gave birth to twin boys. As they were being born, one child stuck his hand out. The midwife tied a red thread around it, saying, “This is the firstborn.” 
Suddenly, the hand went back in and the other child was born. So they named that child, Perez, which means, “Break out.” Then his brother was born. Because of the bright red thread on his wrist, they named him Zerah, which means “Bright.”