Deuteronomy 25:17

Remember what Amalek did to thee by the way, when ye had come forth from Egypt;

Exodus 17:8-16

Then came Amalek, and fought with Israel in Rephidim.

Numbers 24:20

And when he looked on Amalek, he took up his parable, and said, Amalek was the first of the nations, but his latter end shall be that he shall perish for ever.

Numbers 25:17-18

Distress the Midianites, and smite them:

Treasury of Scripture Knowledge

Summary

Remember what Amalek did unto thee by the way, when ye were come forth out of Egypt;

Bible References

General references

Exodus 17:8
Then came Amalek, and fought with Israel in Rephidim.
Numbers 24:20
And when he looked on Amalek, he took up his parable, and said, Amalek was the first of the nations, but his latter end shall be that he shall perish for ever.
Numbers 25:17
Distress the Midianites, and smite them: