I’ve not verified this with anyone, but I think the first recorded Thanksgiving Day occurred under King David’s rule and is found in 1 Chronicles 16. The day was a community-wide, or more accurately, a national occasion, with worship and feasting and music of every kind, including songs. One is recorded for us, so we know the focus of this thanksgiving was God.
Here are the key parts of the passage (I’m leaving the verse numbers in place so you can see what I’ve included):
1 And they brought in the ark of God and placed it inside the tent which David had pitched for it, and they offered burnt offerings and peace offerings before God. 2 When David had finished offering the burnt offering and the peace offerings, he blessed the people in the name of the LORD. 3 He distributed to everyone of Israel, both man and woman, to everyone a loaf of bread and a portion of meat and a raisin cake.
4 He appointed some of the Levites as ministers before the ark of the LORD, even to celebrate and to thank and praise the LORD God of Israel
7 Then on that day David first assigned Asaph [who wrote some of the psalms recorded in Scripture] and his relatives to give thanks to the LORD.
8 Oh give thanks to the LORD, call upon His name;
Make known His deeds among the peoples.
9 Sing to Him, sing praises to Him;
Speak of all His wonders.
10 Glory in His holy name;
Let the heart of those who seek the LORD be glad.
11 Seek the LORD and His strength;
Seek His face continually.
12 Remember His wonderful deeds which He has done,
His marvels and the judgments from His mouth,
13 O seed of Israel His servant,
Sons of Jacob, His chosen ones!
14 He is the LORD our God;
His judgments are in all the earth.
15 Remember His covenant forever,
The word which He commanded to a thousand generations,
23 Sing to the LORD, all the earth;
Proclaim good tidings of His salvation from day to day.
24 Tell of His glory among the nations,
His wonderful deeds among all the peoples.
25 For great is the LORD, and greatly to be praised;
He also is to be feared above all gods.
26 For all the gods of the peoples are idols,
But the LORD made the heavens.
27 Splendor and majesty are before Him,
Strength and joy are in His place.
28 Ascribe to the LORD, O families of the peoples,
Ascribe to the LORD glory and strength.
29 Ascribe to the LORD the glory due His name;
Bring an offering, and come before Him;
Worship the LORD in holy array.
30 Tremble before Him, all the earth;
Indeed, the world is firmly established, it will not be moved.
31 Let the heavens be glad, and let the earth rejoice;
And let them say among the nations, “The LORD reigns.”
32 Let the sea roar, and all it contains;
Let the field exult, and all that is in it.
33 Then the trees of the forest will sing for joy before the LORD;
For He is coming to judge the earth.
34 O give thanks to the LORD, for He is good;
For His lovingkindness is everlasting.
35 Then say, “Save us, O God of our salvation,
And gather us and deliver us from the nations,
To give thanks to Your holy name,
And glory in Your praise.”
36 Blessed be the LORD, the God of Israel,
From everlasting even to everlasting.
Then all the people said, “Amen,” and praised the LORD.
Now that’s Thanksgiving!