Numbers 4:13

And they shall take away the ashes from the altar, and spread a purple cloth thereon:

Cross-reference

In Numbers 4:6-9, the ark, table, and lampstand are covered with blue cloths — similar procedure as covering the altar here, but with different colors.

In Numbers 4:11, the golden altar is covered with blue cloth — the same covering method but a different color than the purple used here.

In Numbers 4:12, utensils are covered with blue cloth and badgers' skins — here the altar is covered with purple, showing parallel covering procedures.

Exodus 27:3–5 Historical context

Exodus 27:3-5 describes the bronze altar's utensils and grating — the same altar that is covered here during transport.

Exodus 27:7 Historical context

Exodus 27:7 describes staves for carrying the altar — the same altar is covered here before transport, implying the use of those staves.

Leviticus 6:12 Historical context

Leviticus 6:12 commands the fire to burn continually on the altar — the same altar from which ashes are removed and which is covered here.

Leviticus 6:13 Historical context

Leviticus 6:13 restates that the fire on the altar must never go out — the altar covered here is the one with the perpetual fire.

Exodus 39:1 Related theme

Exodus 39:1 lists purple among the colors for service cloths — the same purple cloth used to cover the altar here.