Exodus 23:18

14 Three times a year you are to celebrate a feast to Me.

15 You are to keep the Feast of Unleavened Bread as I commanded you: At the appointed time in the month of Abib you are to eat unleavened bread for seven days, because that was the month you came out of Egypt. No one may appear before Me empty-handed.

16 You are also to keep the Feast of Harvest with the firstfruits of the produce from what you sow in the field. And keep the Feast of Ingathering at the end of the year, when you gather your produce from the field.

17 Three times a year all your males are to appear before the Lord GOD.

18 You must not offer the blood of My sacrifices with anything leavened, nor may the fat of My feast remain until morning.

19 Bring the best of the firstfruits of your soil to the house of the LORD your God. You must not cook a young goat in its mother’s milk.

20 Behold, I am sending an angel before you to protect you along the way and to bring you to the place I have prepared.

21 Pay attention to him and listen to his voice; do not defy him, for he will not forgive rebellion, since My Name is in him.

22 But if you will listen carefully to his voice and do everything I say, I will be an enemy to your enemies and a foe to your foes.

Read all of Exodus 23