Watchman Nee emphasizes the necessity of having a flexible spirit to discern and fulfill God's will, asserting that a rigid spirit hinders the movement of the Holy Spirit and leads to spiritual stagnation. He illustrates that just as Philip was guided by the Spirit, believers must remain sensitive and adaptable to God's leading, responding to the needs of others with an open spirit. Nee warns that a closed spirit can prevent the transmission of spiritual truth and that one must maintain a high spiritual standard to avoid descending into failure. He stresses the importance of cooperation between the spirit and the mind, as neglecting this relationship can lead to spiritual weakness and misinterpretation of God's messages. Ultimately, he calls for believers to live at the highest spiritual level they have attained to experience God's power fully.