According to the New Oxford American Dictionary, complete is defined as “having all the necessary or appropriate parts.” In this case, the “necessary or appropriate parts” are everything we need to know, love, obey, and worship God, as well as everything we need to love others. Of course, this is my own statement and I don’t know everything that we could possibly need for life and godliness. The good news is that God knows everything we would possibly need, and He has promised that His word is sufficient.
[10] According to the grace of God given to me, like a skilled master builder I laid a foundation, and someone else is building upon it. Let each one take care how he builds upon it. [11] For no one can lay a foundation other than that which is laid, which is Jesus Christ. (ESV)
Here, Paul lays a foundation for the believers in Corinth. According to this passage, what is the foundation of our faith? The foundation is Jesus Christ.
[2] For I decided to know nothing among you except Jesus Christ and him crucified. (ESV)
The foundation which Paul described in 3:11 is the message of the life, death, and resurrection of Jesus Christ. Paul isn’t just saying that our faith rests on Jesus, he’s saying that the foundation of the Church is this message. And this message is none other than the Gospel, not the four gospel books, but the message of God’s salvation. When Paul planted a church, he wanted them to know the Gospel above all else. And this good news, this message of grace, is in every book of the Bible.
[17] “Do not think that I have come to abolish the Law or the Prophets; I have not come to abolish them but to fulfill them. [18] For truly, I say to you, until heaven and earth pass away, not an iota, not a dot, will pass from the Law until all is accomplished. [19] Therefore whoever relaxes one of the least of these commandments and teaches others to do the same will be called least in the kingdom of heaven, but whoever does them and teaches them will be called great in the kingdom of heaven. [20] For I tell you, unless your righteousness exceeds that of the scribes and Pharisees, you will never enter the kingdom of heaven. (ESV)
[24] “Everyone then who hears these words of mine and does them will be like a wise man who built his house on the rock. [25] And the rain fell, and the floods came, and the winds blew and beat on that house, but it did not fall, because it had been founded on the rock. [26] And everyone who hears these words of mine and does not do them will be like a foolish man who built his house on the sand. [27] And the rain fell, and the floods came, and the winds blew and beat against that house, and it fell, and great was the fall of it.” (ESV)
Jesus begins the sermon on the mount with a profound claim and a warning. The claim is this: All of scripture is about Jesus and He is the fulfilment of it. The warning is this: Do not relax, unwind, or loosen God’s word. Jesus later closes this sermon in chapter 7 with a related message. He describes two men: one man who builds his house on the foundation of “these words of mine”, and one man who does not. “These words of mine” are Jesus' words and therefore God’s word (John 12:49). By saying the Law and Prophets, Jesus is referring to the entire old testament; the same old testament that was read in the synogogues at that time.
[4] As you come to him, a living stone rejected by men but in the sight of God chosen and precious, [5] you yourselves like living stones are being built up as a spiritual house, to be a holy priesthood, to offer spiritual sacrifices acceptable to God through Jesus Christ. [6] For it stands in Scripture: “Behold, I am laying in Zion a stone, a cornerstone chosen and precious, and whoever believes in him will not be put to shame.” (ESV)