1 Pet 2:6-8 Wherefore also it is contained in the scripture, Behold, I lay in Sion a chief corner stone, elect, precious: and he that believeth on him shall not be confounded. 7 Unto you therefore which believe he is precious: but unto them which be disobedient, the stone which the builders disallowed, the same is made the head of the corner, 8 And a stone of stumbling, and a rock of offence, even to them which stumble at the word, being disobedient: whereunto also they were appointed.

Here the building of a house is compared to building up the body of Christ (the bride), our individual spiritual life in which Jesus is the chief cornerstone (akrogoniaios; the extreme corner). This word comes from the root word akron (tip, top, or uttermost part) and it identifies Jesus as the head of the true church. Peter quoted Isaiah 28:16 and said that anyone who believes on Jesus (makes Him their cornerstone) will not be confounded (kataischuno; shamed; disgraced; dishonored).

Now, if we look at another definition of cornerstone we’ll see what we believe in. Webster says that it’s a stone that lies at the corner of two walls and serves to unite them. Specifically, it’s a stone built into a corner of the foundation of an important edifice, as the actual or nominal starting point of the building. So, look at Jesus as God’s cornerstone for His bride (the important edifice) and He lies between two walls (God and Man) as the stone that unites them.

Eph 2:21-22 We who believe are carefully joined together with Christ as parts of a beautiful, constantly growing temple for God. 22 And you also are joined with him and with each other by the Spirit and are part of this dwelling place of God.

Look at the alternative to accepting Him as the cornerstone:

1 Peter 2:7-8 Unto you therefore which believe he is precious: but unto them which be disobedient, the stone which the builders disallowed, the same is made the head of the corner, 8 And a stone of stumbling, and a rock of offence, even to them which stumble at the word, being disobedient: whereunto also they were appointed.

Here Peter quoted Psalm 118:22 where the psalmist was speaking of the army of Israel that was hard pressed in battle; it was also prophetic with respect to nonbelievers. In verse 8 the result of rejection is revealed in a quote from Isaiah 8:14; it becomes a stumbling block. There is no neutral position with Jesus. He is either your cornerstone (foundation) or your stumbling block.

Jesus is our Spiritual Foundation, our chief cornerstone upon which we, His bride, are joined together with Him by His Spirit.