One-Page Learn · The Halachos at a glance
הלכות חמץ ומצה
Chametz u'Matzah 5
Sefer Zemanim · What can actually become chametz, the discipline of kneading and watching, and how vessels are purged for Pesach
5
GRAIN SPECIES THAT CAN BECOME CHAMETZ - NO OTHERS
1 MIL
WALK'S WORTH OF REST BEFORE DOUGH IS CHAMETZ
43.2
EGGS - THE LARGEST DOUGH ONE MAY KNEAD
2
BOWLS OF WATER FOR ONE WHO KNEADS AND BAKES
5:1-8What Can Actually Sour
- Five grains only. Wheat, spelt, barley, oats, rye; kitniyot like rice and lentils never leaven, they only decay, even if the dough visibly rises (5:1)
- Fruit juice never leavens. Flour kneaded with wine, milk, honey, oil or juice alone stays permitted all day; one drop of water in the mix and it leavens, faster than water alone (5:2)
- Cooking rules. Wheat or flour cooked in water is full chametz once kernels crack; baked matzah may be re-cooked freely; throwing flour into fully boiling water works by law but custom forbids it (5:3-5)
- The kernel in the pot. Grain found in a cooked dish: cracked open, the whole dish is forbidden; uncracked, burn the kernel and the dish may be eaten, for uncracked soaked grain is chametz only by rabbinic decree (5:8)
RememberOnly the grains that could have been matzah can become chametz, and only water can take them there
5:9-16Motion Against Rest
- Watch from the harvest. "Keep watch over the matzot": Pesach grain is guarded from water after cutting; grain that sank in a river may not even be kept, it is sold in small lots with disclosure (5:9)
- The drip defense. Grain under a continuing leak does not leaven even all day; the leak stops, and one mil of stillness makes it chametz (5:10)
- Kneading discipline. No dough above the challah measure, no hot or sun-warmed water, only water drawn the day before and rested overnight; a loaf kneaded with such forbidden water is itself forbidden (5:11)
- Lenient after the fact. Kneaded in the sun, hands not cooled, dough oversized: forbidden to do, but the baked loaf is permitted b'dieved (5:12)
- The clap test. Busy hands keep dough kosher all day; once rested a mil, or if it answers a clap with a hollow sound, it is chametz and burned at once, and a silent twin dough that rested equally long burns with it (5:13-14)
RememberDough never leavens under working hands; the clock only runs while you rest
5:17-26Bran, Dips, and the Memory of Vessels
- Feed and cosmetics. No soaking bran for chickens unattended; feeding is fine while they peck or you stir within a mil; dry bran may be rubbed on skin, but chewed wheat on a wound becomes chametz (5:17-19)
- Flour in dips. Flour in charoset is burned immediately, its vinegar leavens fast; flour in mustard is eaten immediately; spices, sesame and poppy in dough are fine, though the first night's mitzvah matzah must be plain water dough, poor man's bread (5:19-20)
- Purging by kind. As a vessel absorbed, so it releases: metal and stone kli rishon by boiling within, kli sheni by pouring boiling water over; then rinse cold and use for matzah (5:23-24)
- Earthenware never purges. Glazed or plain, used hot with chametz it cannot be kashered; set it aside until after Pesach, when it may be used again; yeast and charoset vessels are barred even from cold use (5:21, 5:25)
RememberWhat soaked in through fire comes out through fire, but clay keeps its past; retire it, don't smash it