Numbers 9:9-11

9The Lord spoke to Moses, saying, 10Speak to the people of Israel, saying, If any one of you or of your descendants is unclean through touching a dead body, or is on a long journey, he shall still keep the Passover to the Lord. 11 aIn the second month on the fourteenth day at twilight they shall keep it. bThey shall eat it with unleavened bread and bitter herbs.
Copyright information for ESV