Charles Spurgeon Commentary John 17:21

"that they may all be one; even as thou, Father, [art] in me, and I in thee, that they also may be in us: that the world may believe that thou didst send me." — John 17:21 (ASV)

That they all may be one, as you, Father, are in me, and I in you, that they also may be one in us; that the world may believe that you have sent me.

I wish that we could see more of this blessed unity, yet it does exist, even if we cannot see it. Wherever there is any true spiritual life—it does not matter how much denominational divisions may mar it—there is, and always must be, an essential unity.

All Christians are one family in Christ. I do not mean all who call themselves Christians, but all who really are believers in Christ. The inner life is one, the source of that life is one, the nourishment of that life is one, and the end of that life is one, so that all who possess it must be one—one in Christ, and one with one another, even as Christ is one with the Father.

As thou, Father, art in me, and I in thee, that they also may be one in us: that the world may believe that thou hast sent me.

Christ would have all his people joined in communion with himself, and with his Father; and when that is the case, then will people know that Christ came into the world for a definite purpose: that the world may believe that thou hast sent me.

As you, Father, are in me, and I in you, that they also may be one in us: that the world may believe that you have sent me.

Can the world believe in Christ until his Church becomes more manifestly one? I fear not, so let us each one aim at the true unity of the one Church of Jesus Christ. There are some who aim at this by separating themselves from everybody else, but I do not see how they promote unity in that way. I clearly and painfully see how they increase divisions and multiply strife wherever they go. But let us, beloved, to the utmost of our power, promote the unity of the body of Christ.

That they all may be one; as thou, Father, art in me, and I in thee, that they also may be one in us: that the world may believe that thou hast sent me. (John 17:21)

And when Christians, being one in Christ, and one in the truth, become more manifestly one in heart, and life, and faith, what glad days we may hope to see!

That they all may be one;

This is Christ's prayer for all those who shall believe on him, that they may be converted, and brought into the one Church together with those who are already there: that they all may be one.

That they all may be one, –

That is the great prayer of Christ. There are not two churches, but one Church. Christ is not the Head of two bodies, he has but one mystical body. There is but one Bridegroom, and there is but one bride, – that bride is his indivisible Church. Hence his prayer, That they all may be one; –