Leviticus 24:5

2 Give orders to the children of Israel to give you clean olive oil for the light, so that a light may be burning at all times,

3 Outside the veil of the ark in the Tent of meeting; let Aaron see that it is burning from evening till morning at all times before the Lord: it is a rule for ever through all your generations.

4 Let Aaron put the lights in order on the support before the Lord at all times.

5 And take the best meal and make twelve cakes of it, a fifth part of an ephah in every cake.

6 And put them in two lines, six in a line, on the holy table before the Lord.

7 And on the lines of cakes put clean sweet-smelling spices, for a sign on the bread, an offering made by fire to the Lord.

8 Every Sabbath day regularly, the priest is to put it in order before the Lord: it is offered for the children of Israel, an agreement made for ever.