Harry Ironside emphasizes the importance of caring for God's 'fruit-trees,' which symbolize His servants, while being vigilant against false teachings and harmful influences. He draws parallels from Deuteronomy 20:19-20, urging believers to discern between those who bear good fruit and those who do not, advocating for a spirit of love and correction rather than harsh judgment. Ironside highlights the need for spiritual discernment to avoid damaging genuine believers while actively opposing falsehoods that threaten the faith. He encourages a nurturing approach, as exemplified by Priscilla and Aquila's gentle correction of Apollos, rather than a critical spirit that could harm fellow Christians. Ultimately, he calls for believers to sharpen their focus on combating sin and error while protecting and uplifting those who are truly serving God.