The Holy Spirit is literally telling us not to be ignorant. A Day is with the Lord as 1,000 years. The future Day with the Lord on earth is a literal 1,000 year period. That is not taking a single verse out of context. 2 Peter 3:8 is comparing a symbolic phrase (with the Lord) to a literal (1,000 years) God is still a patient God. That is using Scripture to interpret Scripture. The third Scripture is found in Genesis 2. All the prophecy about the Day of the Lord, the Day with the Lord is dealing with a future 1,000 year Millennium with Jesus on the earth. Even the 4th Commandment is looking back at the beginning and is prophetic about that future Day with the Lord. That is not me just making things up. Others throughout history have pointed that out. Even the Psalmist declared that about the Lord in Psalms 90:4.
You avoided an answer from Scripture, so you have no proof the Day of the Lord is a single 24 hour period. You assume your theology without written proof from the Word. Peter is quoting Psalms 90:2-6
"Before the mountains were brought forth, or ever thou hadst formed the earth and the world, even from everlasting to everlasting, thou art God. Thou turnest man to destruction; and sayest, Return, ye children of men. For a thousand years in thy sight are but as yesterday when it is past, and as a watch in the night. Thou carriest them away as with a flood; they are as a sleep: in the morning they are like grass which groweth up. In the morning it flourisheth, and groweth up; in the evening it is cut down, and withereth."
There is literally nothing in there about God's patience. According to your logic, Peter is misquoting the Psalmist and talking about God's patience out of context.
The point is people dogmatically state 2 Peter 3:8 is not about time at all, and hypocritically state day means 24 hours, anyways. You realize that saying day in those verses has to mean a literal 24 hour period is an assumption and adding to God's Word? In fact declaring that time is not even relative to God, and to prove that "we will state" that "day" is a literal 24 hour period that does not concern God one bit, that is a lot of added assumption and personal opinion.