2Corinthians 7 begins with this:

"Having therefore these promises, dearly beloved..." - 2 Corinthians 7:1 KJV

What promises is it talking about?

2 Corinthians 6 tells us what these promises are.

"… as God hath said, I will dwell in them, and walk in them; and I will be their God, and they shall be my people." - 2 Corinthians 6:16 KJV

Where did God say this?

Leviticus 26:12; Jeremiah 32:38; Ezekiel 37:27

"And I will set my tabernacle among you: and my soul shall not abhor you. And I will walk among you, and will be your God, and ye shall be my people." - Leviticus 26:11-12 KJV

"And they shall be my people, and I will be their God... And I will make an everlasting covenant with them, that I will not turn away from them, to do them good..." - Jeremiah 32:38, 40 KJV

"Neither shall they defile themselves any more with their idols, nor with their detestable things, nor with any of their transgressions: but I will save them out of all their dwellingplaces, wherein they have sinned, and will cleanse them: so shall they be my people, and I will be their God... Moreover I will make a covenant of peace with them; it shall be an everlasting covenant with them: and I will place them, and multiply them, and will set my sanctuary in the midst of them for evermore. My tabernacle also shall be with them: yea, I will be their God, and they shall be my people. And the heathen shall know that I the LORD do sanctify Israel, when my sanctuary shall be in the midst of them for evermore." - Ezekiel 37:23, 26-28 KJV

God makes this promise to us if we will become His dearly beloved, making a covenant with Him to give all of our heart to Him, as He has loved us.

We make this covenant with God when we turn our backs on the world. We repent of our sins, and take on His name Jesus in water baptism. Our covenant with God is complete when we receive His Spirit, the Holy Ghost. (Acts 2:38) We exchange our yoke with the world to yoke ourselves together with God.

"Be ye not unequally yoked together with unbelievers: for what fellowship hath righteousness with unrighteousness? and what communion hath light with darkness? And what concord hath Christ with Belial? or what part hath he that believeth with an infidel?" - 2 Corinthians 6:14-15 KJV

When we have taken the name of Jesus upon ourselves, and are filled with His Spirit, we become the temple of God. Temple is another word for tabernacle.

"And what agreement hath the temple of God with idols? for ye are the temple of the living God; as God hath said, I will dwell in them, and walk in them; and I will be their God, and they shall be my people." - 2 Corinthians 6:16 KJV

We are to leave the world and the things of the world behind when we begin our new life with God.

"Wherefore come out from among them, and be ye separate, saith the Lord, and touch not the unclean thing…" - 2 Corinthians 6:17 KJV

With our greater commitment to God, He makes a commitment to us with His promises.

 "…and I will receive you, and will be a Father unto you, and ye shall be my sons and daughters, saith the Lord Almighty." - 2 Corinthians 6:17-18 KJV

This brings us back to 2 Corinthians 7:1.

"Having therefore these promises, dearly beloved, let us cleanse ourselves from all filthiness of the flesh and spirit [from everything that can defile our body or spirit], perfecting holiness in the fear of God [bringing holiness to completion out of reverence for God]." - 2 Corinthians 7:1 KJV