We  are made sons through Him by adoption and grace, as partaking of His Spirit (for ‘as many as received Him,’ he says, ‘to them gave He power to become children of God, even to them that believe on His Name Jn1:12), and therefore also He is the Truth (saying, ‘I am the Truth,’ and in His address to His Father, He said, ‘Sanctify them through Thy Truth, Thy Word is Truth’ Jn 14:6); but we by imitation become virtuous and sons: — therefore not that we might become such as He, did He say ‘that they may be one as We are;’ but that as He, being the Word, is in His own Father, so that we too, taking an exemplar and looking at Him, might become one towards each other in concord and oneness of spirit, nor be at variance as the Corinthians, but mind the same thing, as those five thousand in the Acts (Acts 4: 4, 32), who were as one.

St. Athanasius, Discourses Against Arians, discourse III, Ch 25, p.404-405..