Exodus 22:1

If a man shall steal an ox, or a sheep. — The flocks and herds of the Israelites constituted their principal property, and hence cattle-stealing is taken as the representative of theft in general.

And kill it, or sell it. — Plainly showing persistence and determination.

Five oxen... four sheep. — The principle of the variation is not clear. Perhaps the theft of an ox was regarded as involving more audacity, and so more guilt, in the thief.