Day of Judgement/Day of Heaven. I put it this way only b/c the discussion here revolves around the rewards of Judgement day which is heaven for all believers...eternal rest.
The number 7 is a number meaning completion, fulfillment one gets this clue from creation which is penned here again in Hebrews and with reason. Hebrews points to the symbolism or parallelism between God resting on the 7th day which later became the Sabbath for mankind and our final rest in heaven.
Hebrews 4:8-11:
For if Joshua had given them rest, God would not have spoken later about another day. 9 There remains, then, a Sabbath-rest for the people of God; 10 for anyone who enters God’s rest also rests from their works,just as God did from his. 11 Let us, therefore, make every effort to enter that rest, so that no one will perish by following their example of disobedience.
The account of Joshua of course follows the commandment of Sabbath-keeping given to Moses. Joshua's rest was to be Canaan (the Promised Land). Our rest is eternal and is in heaven.
Hebrews 11:8-16:
By faith Abraham, when called to go to a place he would later receive as his inheritance, obeyed and went, even though he did not know where he was going. 9 By faith he made his home in the promised land like a stranger in a foreign country; he lived in tents, as did Isaac and Jacob, who were heirs with him of the same promise. 10 For he was looking forward to the city with foundations, whose architect and builder is God. 11 And by faith even Sarah, who was past childbearing age, was enabled to bear children because she considered him faithful who had made the promise. 12 And so from this one man, and he as good as dead, came descendants as numerous as the stars in the sky and as countless as the sand on the seashore.
13 All these people were still living by faith when they died. They did not receive the things promised; they only saw them and welcomed them from a distance, admitting that they were foreigners and strangers on earth. 14 People who say such things show that they are looking for a country of their own. 15 If they had been thinking of the country they had left, they would have had opportunity to return. 16 Instead, they were longing for a better country—a heavenly one. Therefore God is not ashamed to be called their God, for he has prepared a city for them.
Same account...sooo beautiful.