CRRRR-AAA-CK! B-RRRR-UMMMMM!

Lightning exploded overhead, but the blinding flash was quickly swallowed by the thick, dark clouds that covered the top of Mount Sinai. The thunder that followed made its way down the mountain with a low, grumbling sound, shaking rocks loose and sending them tumbling after it.

The ground under Ethan’s sandals vibrated with the rumble. Good one, he thought. He grinned and held his stomach, which was doing some tumbling of its own. Nobody liked lightning more than Ethan did, and this was superlightning.

He glanced around impatiently. Melki was missing all this. Where is he, anyway? He was supposed to meet me at the boundary marker.

Ethan started walking up the path again, picking his way through the brambles that had overgrown it. Every so often he lifted his head to stare at the mountain in front of him —a tower that rose suddenly from the flat desert floor, its granite as dark brown and rough and wrinkled-looking as an old man’s face. He tried to imagine climbing the sheer cliffs, hand over hand, but the path was the only way up the mountain as far as he could see. Narrowing between two large rocks, it twisted and turned up the side until it disappeared into the clouds that had settled on the peak.

Lightning flashed again, and the thunder clapped a few seconds later. Close, Ethan thought, but not close enough. He wanted to see the white-hot bolts, the spiky fingers reaching down from the sky. What else was there to do when you were stuck in the middle of a miserable desert, having to follow a bunch of stupid —

“You there!” It was a man’s voice, calling from somewhere up the path. Ethan dropped his gaze from the mountaintop and saw a muscular-looking, gray-robed Israelite pop from behind a boulder. “What’s your business here?” the man said, scratching his tangle of a beard.

Ethan swallowed. He swallowed again when he saw that the man had a bow in his hand and a quiver of arrows slung on his back.

“I said, what’s your business?” the man repeated. “You should be back in camp, boy.”

Another man, taller and skinnier than the first, stepped from behind the boulder. He seemed more curious than angry, but Ethan noticed he was armed with bow and arrows too. “A visitor?” the second man asked.

“Some kid,” the first man growled. “The last thing we need.”

Ethan glanced back over his shoulder, toward camp. He could see rows and rows of tents, and knots of people here and there, braving the desert sun. But he didn’t see Melki.

He groaned. Melki was good at stuff like this, standing up to adults and speaking his mind. It usually got Melki into trouble, but maybe getting in trouble was better than being a meek little sheep. Lately Ethan was getting tired of being a sheep.

He cleared his throat, which felt as rough and dry as the mountain in front of him looked. “Is —is the boundary around here?” he asked.

The first man raised his bow and pointed it farther up the path. Ethan could see a pile of a dozen or so large stones stacked on top of each other. “That’s the marker,” the man said gruffly.

Ethan wrinkled his nose. Not exactly what I expected. The adults had made such a big deal of the boundary, he’d almost thought the marker would look like one of the giant stone archways they’d left back in Egypt, guarded by statues of weird-looking animals or dead pharaohs. But it was just a pile of rocks.

“You’ve gone as far as you need to go, boy,” the first man warned.

The taller man looked at Ethan, giving him an “aren’t you a cute child” smile that made Ethan wince. “In case you haven’t heard, son, God has told Moses that no one is to go up the mountain.”

I heard, Ethan thought. Everybody who hasn’t been in a cave for the past week has heard.

“So you’re . . . guarding the boundary?” Ethan ventured.

“That’s the general idea,” said the first man, reaching back over his shoulder and pulling an arrow from the quiver. He fitted the arrow to the bowstring and narrowed his eyes at Ethan.

Ethan gulped.

The taller man frowned at his companion. “Come on,” he scolded. “You’re gonna scare him. He’s just a boy.” He turned toward Ethan. “How old are you, son? Eight?”

Ethan felt his cheeks turn red. “Nine and a half,” he mumbled.

“Well, I’m sure your family has chores for you to do. Run along, now. Got to follow the rules, you know.”

Ethan clenched his teeth at the word. Rules. That’s all we have anymore. Kicking a stone off the path, he turned and slowly started walking back toward camp.

He hadn’t gone far when another lightning flash lit up the sky. He turned to the mountain but couldn’t see anything through the clouds. Disappointed, he stood there as the thunder echoed in his ears.

“Hey,” came a sudden voice from behind him. “Guess I’m a little late, huh?”

Whirling, Ethan saw Melki standing in the middle of the path. “A little late?” Ethan cried. “I had to stand up to the boundary guards myself. They have bows and arrows and —”

Melki snorted. “Oooh, I’m scared. What are they, a couple of guys who used to make bricks in Egypt? Not exactly soldiers. They probably couldn’t hit the broad side of a pyramid with their arrows.”

Ethan looked up at the sky, searching in vain for more lightning. “Maybe not. But they won’t let us get any closer. We’ll have to watch from here.”

Melki sighed long and loud but found a broad, flat rock where they could sit. They waited in silence for a minute or so, until lightning flared again behind the clouds.

After the thunder faded, Ethan glanced over at his best friend, who was poking a stick into a crack in the rock. “Could you see it that time?”

“Just barely,” Melki answered, obviously unimpressed. “I’m telling you, we need to get closer if we really want to see.”

“We can’t get any closer!” Ethan said. “The boundary marker’s right up there. It’s just a pile of rocks, but —”

Melki shook his head. “A pile of rocks!” He picked up a handful of sand and threw it toward the mountain. “All we have to do is walk around it.” He pointed to a small plateau several hundred feet up the mountainside. “That’s where we need to go. We could lie on our backs and stare up through the bottom of the clouds. We’d be able to see everything!”

Ethan looked over at his friend. Wish I could be more like Melki, he thought. It wasn’t just that Melki seemed older, even though they were the same age and almost the same height. It wasn’t just that Melki’s dark hair was curly and wild, as if someone had spilled it on top of his head, and Ethan’s was straight and neatly groomed and boring. It wasn’t just that Melki was broad and muscular, like his father, and Ethan was thin and wiry, like his father.

It was the fact that Melki didn’t have to worry about . . . rules.

“You know we’re not supposed to go past the marker,” Ethan said and then made a sour face. He didn’t like the words that were coming out of his mouth. And he especially didn’t like saying them to Melki. “We have to stay off the mountain until the Lord talks to Moses. You know the rules.”

“Rules!” Melki roared with laughter. “Do you know who you’re starting to sound like?” He lifted his head as high as he could, puffed his chest out, and started stroking an imaginary beard. “Ethan, you know the rules,” he said in a deep, stern voice. “You can’t eat manna that other families have collected. You can’t leave our tent area on the Sabbath. And you can’t go to the bathroom after sundown.”

Ethan snickered and then lowered his head to hide his smile. Melki’s imitation of Father was perfect, but it didn’t seem right to encourage him. “You know my father doesn’t have a rule about going to the bathroom.”

“Maybe not yet,” Melki answered. “But give him time. He has rules for everything else —you said so yourself.”

Ethan sighed. “Yeah, but the rule about the mountain didn’t come from my father. It came from Moses.” He glanced up to see the end of a lightning flash and then looked down again. “He said we can’t set foot on it because God is there, and God is holy. Besides, even if we wanted to climb the mountain, we couldn’t. They wouldn’t let us.” He pointed back over his shoulder toward the guards. “That path is the only way up this side of the mountain, and there’s no way we could get past them without getting caught.”

“We could if we did it at night,” Melki whispered. “There’s a lot more to see here at night anyway.”

“How do you know?” Ethan demanded.

“I snuck out of our tent last night and came over here,” Melki answered. He gave Ethan a sly smile.

Ethan looked up and down the path to make sure no one was coming or going. “Are you crazy?” he asked, keeping his voice low even though no one else was in sight. “Did you —”

“No, I didn’t go on the mountain,” Melki finished. “But I could have. There was only one guard by the boundary marker, and I think he was asleep. But I knew you would want to go with me, so I decided to wait until you were there.”

Well, that’s kind of nice, Ethan thought, sitting a little taller. Melki never waits for anything. Kind of like Leah —

Leah! he thought, suddenly remembering. “Uh-oh,” he said. “My sister’s probably waiting for me.” He got up from the rock. “I’m supposed to meet her by the dead tree, near the stream.”

Melki rolled his eyes but got up too. “Let’s go,” he said. “Wouldn’t want to keep Leah the Law Lover waiting.”

Sweat was trickling down Ethan’s neck and into the scratchy collar of his robe by the time they reached the northern border of the camp. It was nearing the hottest part of the day, and the clouds around Mount Sinai didn’t reach far enough to block the sun. At least being skinny made it easy for Ethan to wind his way through the tight maze of tents, cooking fires, and people. Melki followed, mumbling about the heat and how it had never seemed this hot back in Egypt.

Ethan looked around at the tents, row after row of goatskin shelters in various shades of tan and gray. None of them flapped even a little in the breezeless air. He was glad the Israelites had been in the Sinai Valley for only a few days —not long enough for the camp to take on the sharp, stomach-turning odor of sweat, boiling manna, and animal waste mingled together. But he knew that smell would come soon enough. It always did.

The sun was directly overhead now. Ethan could feel it baking his scalp. “Leah’s going to be mad,” he said. “She told me not to be late, because she didn’t have time to wait for me today.”

Melki snorted again. “Oh, then we’d better hurry,” he said and proceeded to plop himself down right in the middle of the path to the dead tree.

Ethan’s heart seemed to squeeze in his chest. “What are you doing?” he asked, looking around to make sure no one was coming. “Get up!”

“No,” Melki said. “Leah may be your master, but she’s not mine.”

“What are you talking about?” Ethan snapped. He could feel his face turning red. “Leah’s not my master.”

Melki rolled his eyes and shook his head. “Everybody’s your master,” he said with a laugh. “Your father, your mother, your sister, and everyone else who tells you what to do. They say, ‘Do this,’ and you do it. They say, ‘Don’t do this,’ and you don’t do it. It’s like you’re still a slave.”

“I’m as free as you are,” Ethan said. He wanted it to sound like a challenge, but it came out sounding more like a question.

Melki stood up and took a step toward him. “Have you ever told your father how much you hate it out here in the desert, or that you wish you’d never left Egypt?” he asked.

“No,” Ethan answered, looking down at the sand. “Have you?”

Melki laughed. “My father and I talk about it all the time. He hates the wilderness as much as I do! My mother does too.”

“Yeah, but I can’t talk to my family about things like that,” Ethan muttered.

“Why not?” Melki asked. “Because you’re afraid of getting beaten or yelled at, like when you were a slave in Egypt?”

“No,” Ethan answered. He knew his parents would never beat him, and they rarely raised their voices. But that didn’t mean he was free to break the rules, did it?

“A free person can do whatever he wants —including climbing that mountain,” Melki explained. “A slave does what he’s told and follows other people’s rules. So does that make you a free person or a slave?”

Ethan saw a quick vision of himself being led around by three chains —one held by his father, one by his mother, and one by his sister. He closed his eyes and shook his head, trying to erase the image from his mind. “Just drop it, okay?” he told Melki.

Melki laughed again and grabbed Ethan’s arm. “Come on, slave. Your master —I mean, your sister —is waiting.”

Ethan dug his sandal into the path and then kicked sand in Melki’s direction. He’s right, Ethan thought. I’m not just mad because he said I’m a slave. I’m mad because he’s right.

Long before they reached the dead tree, Ethan could see Leah waiting. There was her profile —the nose that stuck out a little too far, the chin that didn’t stick out far enough. She was squinting the way she usually did. Altogether she reminded Ethan of some homely, nearsighted bird.

No wonder nobody likes her, he thought. And she just makes it worse with the way she acts.

The closer they got, the more clearly Ethan could see his frowning sister scouring the horizon for a sign of him. Finally her squint settled on the two boys, and her frown deepened. She shook her head as they approached.

Don’t give me a lecture in front of Melki, Ethan warned silently. And don’t tell me how disappointed you are. You’re not my mother.

Sometimes it was hard to remember that himself. Even though Leah was only two years older than he was, Ethan often felt as if he had three parents —the shortest of whom constantly lectured him about rules. The fact that Leah looked a lot like their mother, with her almond-shaped eyes and wavy black hair, didn’t help.

“You promised you would be here before midday,” Leah said, her voice nasal and piercing. “Remember Father’s rule. When you make a promise to someone, you must always keep it.”

Ethan bit his tongue and tried not to look at Melki. He could feel himself blushing again.

Leah picked up a bundle of bone-white clothes from the ground and threw it at Ethan. He lurched to catch it, but it fell to the sand.

“What’s that?” Melki asked.

Leah looked at Melki as if a locust were crawling out of his nose. “It’s Ethan’s Sabbath outfit,” she explained. “We’re on our way to the stream to make our clothes clean —like Moses told us to do.”

Melki snickered. “My father said we didn’t have to clean our clothes again, since we just washed them a week ago.”

Leah ignored him and turned to Ethan. “We have to go now. Mother and Father are already at the stream waiting for us.” She shook her head at Melki and started off toward the stream.

Melki just grinned at her. “Leah the Law Lover,” he said. “She’s got you trained, that’s for sure.”

Ethan set his jaw and bent down to pick up the clothes. “I’ll see you later,” he said. “Come by our tent after supper tonight.” He started to follow Leah, but Melki grabbed his arm.

“Don’t be a slave your whole life,” Melki whispered. “Do something you want to do.” Then he pointed to the mountain and smiled.

Just then the lightning flashed. “I’ll think about it,” Ethan replied as he started off after Leah. “You can count on that.”