'Proof' in the Bible

It was because I entertained this confidence that I intended to visit you before going elsewhere--so that you might receive a twofold proof of God's favour--

And we send with them our brother, of whose zeal we have had frequent proof in many matters, and who is now more zealous than ever through the strong confidence which he has in you.

Exhibit therefore to the Churches a proof of your love, and a justification of our boasting to these brethren about you.

For, by the practical proof of it which you exhibit in this service, you cause God to be extolled for your fidelity to your professed adherence to the Good News of the Christ, and for the liberality of your contributions for them and for all who are in need,

since you want a practical proof of the fact that Christ speaks by my lips--He who is not feeble towards you, but powerful among you.