Can Christians learn any wisdom from other religions? Certainly! Our own Scriptures tell us that the God who spoke in many and various ways to our Jewish fathers (Heb 1:1) has not left himself without a witness among the Gentile nations. (Rom 1:19-20; Acts 17:22-28)
There are at least three good reasons for Christians to study other religions.
First, to appreciate our own religion better by contrast. We fallen creatures need contrast to appreciate anything. We appreciate life by death, pleasure by pain, light by darkness, dogs by cats, cats by dogs, men by women, women by men, and perfect religion by imperfect religion.
Second, to reinforce and deepen our understanding of similar aspects of our own religion. For instance, Confucius can teach us much about practical social, moral and cosmic harmony; Lao-tzu about God’s quiet, invisible, yielding power in nature; Buddha about the importance of silence and meditation; and, above all, Muhammad, about submission (Islam) to God and his will. However, great caution and discernment are needed, especially if these teachings are not just studied from without but integrated into one’s life from within.
Third, simply to seek and find truth wherever it may be. All truth is God’s truth. We do not know where truth is until we look. So we should look everywhere, if we value truth, like a parent in search of precious children.’
(Handbook of Apologetics)