Some schoolmasters may be viewed as disciplinarians. I think, however, we should see the work of the Holy Spirit here. He convicts us of sin and leads us to Christ. This is not the impersonal law. It's the personal approach of the Holy Spirit. In grace and mercy, He shows us how far we have fallen short of God's perfect standard so that He might gently lead us to the Cross of Christ, the place where we receive the forgiveness of all our sins.
In Galatians 4:6, we learn that ‘God has sent the Spirit of His Son into our hearts.’ The Spirit is not a reward which we earn by being good people. We are bad people who have broken God's law. The Spirit is God’s gift (Titus 3:5). The Spirit is not a reward which we earn because of our good works. Paul connects the gift of the Spirit with Christ’s death for us and our faith in Christ (Galatians 3:13-14).
When the Spirit brings us to Christ our Saviour, He takes us through a process which could be described as disciplinarian. We could look at His work in this way - so long as we see much more of divine grace in this than we would normally associate with the word "disciplinarian"!
The Spirit strips us of our human pride. He leads us to come to Christ with humility. When the Spirit has done His work in our hearts, we do not come to God with our religion in one hand and our morality in the other, insisting that we deserve to be blessed by Him. We look away from ourselves to Christ - ‘Nothing in my hand I bring, simply to Thy Cross I cling.’ All pride in ourselves must be brought to Christ’s Cross as we humbly pray, ‘Spirit of the living God, fall afresh on me, break me, melt me, mould me, fill me.’
Let's look beyond the idea of the law as a disciplinarian. Let's give thanks to God. He has given His Spirit to us. Let’s give ourselves to Him - to ‘be filled with the Spirit’(Ephesians 5:18).