An excellent book on this subject would be "The Normal Christian Life" by Watchman Nee which can be accessed online. There is a chapter dedicated to "Walking after the Spirit". However, it is impossible to walk after the Spirit without the flesh being dealt with by the cross, and Brother Nee goes into great detail on this in the previous chapters.
Below is a segment from the book "The Normal Christian Life."
THE FOURTH STEP: "WALK ... AFTER THE SPIRIT
" For what the law could not do, in that it was weak through the flesh, God, sending his own Son in the likeness of sinful flesh and as an offering for sin, condemned sin in the flesh: that the ordinance of the law might be fulfilled in us, who walk not after the flesh, but after the Spirit " (Rom. 8. 3, 4). Every careful reader of these two verses will see that there are two things presented here. They are, firstly, what the Lord Jesus has done for us, and secondly, what the Holy Spirit will do in us. " The flesh " is " weak " ; consequently the ordinance of the law cannot be fulfilled in us " after the flesh ". (Remember, it is again here a question not of salvation but of pleasing God.) Now, because of our inability God took two steps.
In the first place, He intervened to deal with the heart of our problem. He sent His Son in the flesh, who died for sin and in doing so " condemned sin in the flesh ". That is to say, He took to death representatively all that belonged to the old creation in us, whether we speak of it as ' our old man', the flesh or the carnal ' I '. Thus God struck at the very root of our trouble by removing the fundamental ground of our weakness. This was the first step. But still " the ordinance of the law " remained to be fulfilled " in us ". How could this be done? It required God's further provision of the indwelling Holy Spirit. It is He who is sent to take care of the inward side of this thing, and He is able to do so, we are told, as we " walk ... after the Spirit ". What does it mean to walk after the Spirit? It means two things. Firstly, it is not a work; it is a walk. Praise God, the burdensome and fruitless effort I involved myself in when I sought 'in the flesh' to please God gives place to a blessed and restful dependence on " his working, which worketh in me mightily " (Col. 1. 29). That is why Paul contrasts the " works " of the flesh with the fruit " of the Spirit (Gal. 5. 19, 22).
Then secondly, to "walk after" implies subjection. Walking after the flesh means that I yield to the dictates of the flesh, and the following verses in Romans 8. 5 - 8 make clear where that leads me. It only brings me into conflict with God. To walk after the Spirit is to be subject to the Spirit. There is one thing that the man who walks after the Spirit cannot do, and that is be independent of Him. I must be subject to the Holy Spirit. The initiative of my life must be with Him. Only as I yield myself to obey Him shall I find the " law of the Spirit of life " in full operation and the " ordinance of the law " (all that I have been trying to do to please God) being fulfilled-no longer by me but in me. " As many as are led by the Spirit of God, these are sons of God " (Rom. 8. 14). We are all familiar with the words of the benediction in 2 Corinthians 13. 14: " The grace of the Lord Jesus Christ, and the love of God, and the communion of the Holy Ghost, be with you all ". The love of God is the source of all spiritual blessing ; the grace of the Lord Jesus has made it possible for that spiritual wealth to become ours; and the communion of the Holy Ghost is the means whereby it is imparted to us.
Love is something hidden in the heart of God ; grace is that love expressed and made available in the Son; communion is the impartation of that grace by the Spirit. What the Father has devised concerning us the Son has accomplished for us, and now the Holy Spirit communicates it to us. When therefore we discover something fresh that the Lord Jesus has procured for us in His Cross, let us, for its realisation, look in the direction that God has indicated, and, by our steadfast attitude of subjection and obedience to the Holy Spirit, keep wide open the way for Him to impart it to us. That is His ministry. He has come for that very purpose-that He may make real in us all that is ours in Christ. We have learned in China that, when leading a soul to Christ, we must be very thorough, for there is no certainty when he will again have the help of other Christians. We always seek to make it clear to a new believer that, when he has asked the Lord to forgive his sins and to come into his life, his heart has become the residence of a living Person.
The Holy Spirit of God is now within him, to open to him the Scriptures that he may find Christ there, to direct his prayer, to govern his life, and to reproduce in him the character of his Lord. I went, late one summer, for a prolonged period of rest to a hill-resort where accommodation was difficult to obtain, and while there it was necessary for me to sleep in one house and take my meals in another, the latter being the home of a mechanic and his wife. For the first two weeks of my visit, apart from asking a blessing at each meal, I said nothing to my hosts about the Gospel; and then one day my opportunity came to tell them about the Lord Jesus. They were ready to listen and to come to Him in simple faith for the forgiveness of their sins. They were born again, and a new light and joy came into their lives, for theirs was a real conversion. I took care to make clear to them what had happened, and then, as the weather turned colder, the time came for me to leave them and return to Shanghai.
During the cold winter months the man was in the habit of drinking wine with his meals, and he was apt to do so to excess. After my departure, with the return of the cold weather, the wine appeared on the table again, and that day, as he had become accustomed to do, the husband bowed his head to return thanks for the mealbut no words would come. After one or two vain attempts he turned to his wife. 'What is wrong?' he asked. 'Why cannot we pray to-day? Fetch the Bible and see what it has to say about wine-drinking.' I had left a copy of the Scriptures with them, but though the wife could read she was ignorant of the Word, and she turned the pages in vain seeking for light on the subject. They did not know how to consult God's Book and it was impossible to consult God'smessenger, for I was many miles away and it might be months before they could see me. 'Just drink your wine', said his wife. 'We'll refer the matter to brother Nee at the first opportunity.' But still the man found he just could not return thanks to the Lord for that wine. 'Take it away!' he said at length; and when she had done so, together they asked a blessing on their meal.
When eventually the man was able to visit Shanghai he told me the story. Using an expression familiar in Chinese: 'Brother Nee', he said, 'Resident Boss* wouldn't let me have that drink! ' ' Very good, brother', I said. 'You always listen to Resident Boss!' Many of us know that Christ is our life. We believe that the Spirit of God is resident in us, but this fact has little effect upon our behaviour. The question is, do we know Him as a living Person, and do we know Him as Boss '?
'Resident Boss'-The author's own rendering of Ii-mien tang-chia tih.-ED.