Ye are of your father the devil, and the lusts of your father ye will do...
Jesus spoke to these people in the New Testament and declared their father was the devil. And also we readRomans 9:8
That is, They which are the children of the flesh, these are not the children of God: but the children of the promise are counted for the seed.
Looking at these, we can see that one cannot say the Father is their father - something must occur for the change in parent.
...but ye have received the Spirit of adoption, whereby we cry, Abba, Father.
Just as we can understand the process here when a child is born to people but becomes the child of others through adoption - so it is with God. There must be an adoption to claim that God is our Father. You must repent and place your faith in Christ alone. For those who have, how do you know God is your Father?Hebrews 12:5-8
And ye have forgotten the exhortation which speaketh unto you as unto children, My son, despise not thou the chastening of the Lord, nor faint when thou art rebuked of him: For whom the Lord loveth he chasteneth, and scourgeth every son whom he receiveth. If ye endure chastening, God dealeth with you as with sons; for what son is he whom the father chasteneth not? But if ye be without chastisement, whereof all are partakers, then are ye bastards, and not sons.
This is a warning to all of us that claim to have God as our Father - are you chastened? It is not my words here, but the Word of God, that if you are not, you are not His.