NOTES for Ti2 2:13
For Paul it was obvious that Christianity is life with Christ in His Kingdom. It was just as obvious to him that in the Kingdom there is no place for evil or sin. But Paul always remained a realist. He knew very well what human nature is. From his own experience he understood that it is impossible for fallen man not to sin. And one can get rid of sin completely only after the complete transformation of human nature. Meanwhile, the Savior calls each of us to new life, to life in His Kingdom, already now. How is this possible? Obviously, only despite our own sinfulness.
But what does "despite" mean? At the very moment when we give sin a place in our life, we thereby separate ourselves from the Kingdom, from its life. But sometimes this happens apart from our will: in the fallen state we are far from always able to control our own intentions, including those that lead us toward sin. If we sin consciously and do not repent of the sin committed, the Kingdom is closed to us. But another kind of unfaithfulness is also possible: not betrayal, but a mistake, a spiritual breakdown. In this case we do not drown finally in our sin, but it can very well, even if only for a time, overwhelm us completely.
Yet as long as we ourselves do not regard such a state as the norm, sin does not have complete power over us. And that means we are not completely cut off from the Kingdom and its life. What then keeps us in the Kingdom? Obviously, our true "I," which does not agree with the sin overwhelming us. But our faithfulness to the Kingdom and its life still remains incomplete: at the moment when we find ourselves in the power of sin, we are as if inwardly divided. But Christ cannot be divided.
And not only because He bears within Himself the whole fullness of God, but also because His human nature is free from sin. He is an absolutely whole Person. Therefore only on Him can the Kingdom rest. And we will be able to become full helpers to Him only when we become the same kind of whole persons. Of course, we cannot contain God's fullness, but the transformation of our human nature and its deliverance from the power of sin are entirely real. We need only walk the path on which we set out as Christians. To the end.