'Stead' in the Bible

Now then we are ambassadors for Christ, as though God did beseech you by us: we pray you in Christ's stead, be ye reconciled to God.

You learned it from [our representative] Epaphras, our beloved fellow bond-servant, who is a faithful minister of Christ on our behalf

Whom I would have retained with me, that in thy stead he might have ministered unto me in the bonds of the gospel: