As secure as His. Your acceptance rests entirely on Christ, not on your record, so it cannot be shaken by your failures. You are not the eternal Son, but united to Him you are welcomed by the Father with that same settled certainty.
The Grace Answer
This question usually comes from someone tired of feeling like a disappointment to God, bracing for His frown. The answer of the new covenant is better than most believers dare to hope. In Christ, God sees you in His Son.
Paul says God made us accepted in the Beloved. The Beloved is Jesus. Your acceptance is located in Him, not in your track record. That means when the Father looks at you, He is not tallying your failures against a standard you keep missing. He sees you clothed in the righteousness of Christ that was credited to you the moment you believed.
Accepted, not on probation
Feel the difference. Probation means acceptance is conditional and could be revoked by the next mistake. The gospel says you were accepted, past tense, on the basis of someone else’s perfect record. Since your standing rests on Jesus and not on you, it is exactly as secure as He is. He does not fluctuate, so neither does your acceptance.
Consider what it cost to secure that acceptance. It took the life of the Son. God is not going to treat as cheap or reversible something He paid for at that price. Your standing is as valuable and as permanent as the blood that bought it. This does not mean God is blind to your growth or indifferent to your choices. He is a Father, deeply involved, sometimes correcting. That is the difference between an audit and a home. An audit is looking for what you got wrong so it can be held against you. A home has already decided you belong, and deals with your faults as family matters, not as evidence. But correction from a Father who already delights in you is a world away from the cold audit you may have feared. He is not deciding whether to keep you. That was settled at the cross.
So when shame insists God must be shaking His head at you, answer it with the truth. You are accepted in the Beloved. This does not mean you are the eternal Son, or that every distinction between you and Christ dissolves. It means your standing before the Father rests on Him and not on you, so your acceptance is as secure as His. Your job is not to earn that welcome. It is to believe it is already yours.