John 3:16
KJVFor God so loved the world, that he gave his only begotten Son, that whosoever believeth in him should not perish, but have everlasting life.
For God so loved the world that He gave His one and only Son, that everyone who believes in Him shall not perish but have eternal life.
Also in NKJV · ESV What the early church said about John 3:16
How the early church read itRead differently
How it is used today: Used as the whole gospel in one verse: anyone who believes in Jesus receives eternal life as a free gift, by faith and not by works, and many teach that this life, once received, can never be lost.
First spoken: Jesus said this to Nicodemus, a Jewish teacher who came to Him at night (John 3:1-21). A few lines earlier Jesus told him, "unless one is born of water and the Spirit, he cannot enter the kingdom of God" (John 3:5), and in verse 21 He speaks of the one who "does the truth."
The early Christians: Chrysostom reads the verse as God's great love in giving His only Son for ungrateful sinners, which Protestants also teach. But he says believing is not enough without a right life, and Justin Martyr shows that those who believed also promised to live by Christ's teaching and were then baptized, the new birth of John 3:5, as Tertullian and Chrysostom also taught.
“Even if a person believes rightly about the Father, the Son, and the Holy Ghost, if he does not live rightly, his faith will be of no help toward his salvation. Therefore, when He says, "This is life eternal, that they may know You the only true God" in John 17:3, let us not think that the knowledge spoken of is enough for our salvation. Besides this, we also need a very careful life and conduct.” John Chrysostom, Homilies on John
“All who are convinced and believe that what we teach and say is true, and commit to living accordingly, are instructed to pray and ask God for the remission of their past sins with fasting, while we pray and fast with them. Then, they are brought by us to water and are regenerated in the same way we were.” Justin Martyr, First Apology
The difference: Both readings see God's huge love in giving His Son. But today "believes" is often taken to mean trusting Christ apart from works or baptism; the early Christians read it as a faith that is baptized ("born of water and the Spirit," John 3:5) and goes on living rightly, and Chrysostom says faith alone is not enough.