Deut 3:20, Deut 25:19, Heb 4:8-9, Heb 6:17-20
In the Old Testament, God promised to give rest to the Israelites entering the land of Canaan. (Jos 1:13, Deut 3:20, Deut 25:19)
Jos 1:13 Remember the word which Moses the servant of the Lord commanded you, saying, The Lord your God hath given you rest, and hath given you this land.
Deut 3:20 Until the Lord have given rest unto your brethren, as well as unto you, and until they also possess the land which the Lord your God hath given them beyond Jordan: and then shall ye return every man unto his possession, which I have given you.
Deut 25:19 Therefore it shall be, when the Lord thy God hath given thee rest from all thine enemies round about, in the land which the Lord thy God giveth thee for an inheritance to possess it, that thou shalt blot out the remembrance of Amalek from under heaven; thou shalt not forget it.
The rest God gave to the Israelites in the Old Testament is not a perfect and eternal rest. (Heb 4:8-9)
Heb 4:8 For if Jesus had given them rest, then would he not afterward have spoken of another day. 9 There remaineth therefore a rest to the people of God.
God has given us complete and eternal rest through Jesus, the Christ. (Heb 6:17-20)
Heb 6:17 Wherein God, willing more abundantly to shew unto the heirs of promise the immutability of his counsel, confirmed it by an oath: 18 That by two immutable things, in which it was impossible for God to lie, we might have a strong consolation, who have fled for refuge to lay hold upon the hope set before us: 19 Which hope we have as an anchor of the soul, both sure and stedfast, and which entereth into that within the veil; 20 Whither the forerunner is for us entered, even Jesus, made an high priest for ever after the order of Melchisedec.