Deuteronomy 26:3
And thou shalt go unto the priest that shall be in those days, and say unto him, I profess this day unto the LORD thy God, that I am come unto the country which the LORD sware unto our fathers for to give us. And thou shalt go unto the priest that shall be in those days, and say unto him, I profess this day unto the LORD thy God, that I am come unto the country which the LORD sware unto our fathers for to give us.
The verse belongs to the directions for Israel's firstfruits offering, in which the one bringing the offering was to go to the priest serving at that time and make a public declaration before the Lord. That declaration was to profess that he had come into the country which the Lord had sworn to the fathers to give them.
The profession acknowledged that God had fulfilled His promise by bringing the people into the promised land. It belonged to the firstfruits offering as an expression of gratitude for His goodness, for deliverance, and for the gift of the land.
The directions of this chapter set forth the principles of God's kingdom and of His law, teaching that those whom He blesses remain under obligation to obey Him. They call for wholehearted obedience, which brings blessing, and their instruction and importance continue to apply. The firstfruit offering is acceptable only when presented with reverence and gratitude, while presenting it in self-sufficiency, as if God were indebted to the giver, makes it unacceptable.