אֵ֚לֶּה מוֹעֲדֵ֣י יְהוָ֔ה מִקְרָאֵ֖י קֹ֑דֶשׁ אֲשֶׁר־תִּקְרְא֥וּ אֹתָ֖ם בְּמוֹעֲדָֽם׃
These are the appointed seasons of the LORD, even holy convocations, which ye shall proclaim in their appointed season.
Read kabbalistic (mystical) interpretation of Leviticus 23:4: and classical mystical sources.