For many it is so easy to follow the holidays (Feast days) the world celebrates, but God has clearly stated in His word that He despises the feast days man has appointed for himself. If you are busy celebrating Thanksgiving, Christmas, Easter, Halloween then chances are very good you are celebrating feast days God has not appointed for His people to follow. Many cherry pick the holiday they want to celebrate and point to other ones as not of God, and the truth is if God has not appointed it in His word then it is not of Him but of the world (Isaiah 1:13-20) Bring no more vain oblations; incense is an abomination unto me; the new moons and sabbaths, the calling of assemblies, I cannot away with; it is iniquity, even the solemn meeting. Your new moons and your appointed feasts my soul hateth: they are a trouble unto me; I am weary to bear them. And when ye spread forth your hands, I will hide mine eyes from you: yea, when ye make many prayers, I will not hear: your hands are full of blood. Wash you, make you clean; put away the evil of your doings from before mine eyes; cease to do evil; Learn to do well; seek judgment, relieve the oppressed, judge the fatherless, plead for the widow. Come now, and let us reason together, saith the LORD: though your sins be as scarlet, they shall be as white as snow; though they be red like crimson, they shall be as wool. If ye be willing and obedient, ye shall eat the good of the land: But if ye refuse and rebel, ye shall be devoured with the sword: for the mouth of the LORD hath spoken it.

So what are the days our Father wants for us to observe? Fortunately for us God has not left out the appointed feast days He wants His people to observe and it is outlined in Leviticus 23. Other than reading in the word the following link is most helpful to understand the days God has appointed as Holy unto Him

https://www.gotquestions.org/Jewish-feasts.html