Andrew Murray emphasizes the necessity of definite prayer, illustrating how Jesus asked the blind man, 'What wilt thou that I should do unto thee?' to highlight the importance of articulating specific needs in prayer. He argues that vague prayers often lack the power to elicit a response from God, as they do not reflect a true understanding of one's desires or faith. Murray encourages believers to examine their hearts and express their requests clearly, as this not only strengthens their faith but also aligns their will with God's. He asserts that true prayer involves a commitment to seek God's will actively and to expect answers, fostering a deeper relationship with the Father. Ultimately, Murray calls for a prayer life that is both earnest and specific, leading to a more profound experience of God's grace and provision.