The first Thanksgiving Day is traditionally considered to have taken place in November of 1621, after the first Christian settlers to North America survived the winter, and God blessed them with a bountiful harvest in preparation of their second winter. These simple Christian people thanked God for His mercy and help unto them, and gave this example to all future generations of setting aside time to thank the Almighty God for His benevolence.
It was not a holiday started or created for religious purposes, nor does it have any connection to idolatry, pagan worship, or worship of saints, etc. A roast turkey with many side dishes is a traditional meal in the US. This meal has nothing to do with idolatry, or pagan worship. It is no different than any other national or cultural meal, like churrasco, rice and beans, feijoada, or lasagna when having a special meal together with friends and family.
In October of 1789 the first President of the United States issued a proclamation for the first National Day of Thanksgiving*, and in 1863, the sixteenth President of the United States issued a proclamation for a once yearly day of Thanksgiving to God. It was to be celebrated on the fourth Thursday of the month of November, each year.
This National Day of Thanksgiving does nothing to hinder the Work of God, rather if used as intended supports the guidance given to Believers in the Holy Scriptures.
In Philippians 4:6-7 the brethren are directed to, “Be careful for nothing; but in every thing by prayer and supplication with thanksgiving let your requests be made known unto God. And the peace of God, which passeth all understanding, shall keep your hearts and minds through Christ Jesus.”
In 1Thessalonians 5:16-18 the brethren are likewise told to, “Rejoice evermore. Pray without ceasing. In every thing give thanks: for this is the will of God in Christ Jesus concerning you.”
In summary, Thanksgiving Day in the US is a National Holiday set aside by the government, for all citizens to consider the goodness of God, and to render thanks unto Him for all His mercies. No church, religion or denomination was involved in setting up this National Day of Thanksgiving. The brethren who desire to come together with friends and family, to remember the goodness of God, and offer him Praises, Prayers of Supplication and Thanksgiving for all that He does, are free to do so on this day and furthermore everyday as we are directed by God’s Holy Word.
Your brothers in Christ Jesus,
The Council of Elders.