What Does it Mean to Believe in Jesus? William Barclay on John 3:14-15

William Barclay (1907-1978) was Professor of Divinity and Biblical Criticism at Glasgow University in Scotland. He was the author of over fifty books, including seventeen volumes of New Testament commentary in The Daily Study Bible series. I present some of his thoughts on John 3:14-15 because they are so complementary to the thinking of George MacDonald. 

14 Just as Moses lifted up the snake in the wilderness, so the Son of Man must be lifted up,[a] 15 that everyone who believes may have eternal life in him.
— John 3:14-15 (NIV)

Believing in Jesus, writes Barclay, must mean "at least three things." 

"(a) It means believing with all our hearts that God is as Jesus declared him to be...The Jews looked on God as one who imposed his laws upon his people and punished them if they broke them. They looked on God as a judge and on men and women as criminals at his judgment seat. They looked on God as one who demanded sacrifices and offerings; to get into his presence, it was necessary to pay the price laid down. It was hard to think of God not as a judge waiting to exact penalty...but as a Father who longed for nothing so much as to have his erring children come back home. It cost the life and the death of Jesus to communicate that message. And we cannot begin to be Christians until with all our hearts we believe it. 

"(b) How can we be sure that Jesus knew what he was talking about> What guarantee is there that his wonderful good news is true? ...We must believe that Jesus is the Son of God, that in him is the mind of God...

"(c) ...We must stake everything on the fact that what Jesus says is true. Whatever he says, we must do; whenever he commands, we must obey...Every smallest action in life must be done in unquestioning obedience to him.

"So, belief in Jesus has these three elements -- belief that God is our loving Father, belief that Jesus is the son of God...and unswerving and unquestioning obedience to Jesus."