The Bible has predicted it, and it is the expectation of all christians that 'the knowledge of God shall erelong cover this earth as the waters cover the sea.' The Bible has predicted it, and it is also the expectation of all christians, that a day is coming in the progress of this worlds history, when all the nations and individuals of our race shall feel the power and rejoice in the blessings of the gospel of Christ; - when the ignorance and fears and cruelties of idolatry shall be emptied out of the hearts of men, and the knowledge and hopes and charities of the gospel shall come in and take their place, - when all war and oppression and slavery shall be abolished, and Africa shall remember and turn unto the Lord, 'and all the kindreds of the nations shall worship before Him.' Ps. XXII, 27.<br><br>When we fix our thoughts on this mighty change and contemplate it as a great fact infallibly to be realized, we are irresistibly led to ask, How is this change to be effected? By what power? Through what means? Where is the power that is to 'break every yoke,' set free every slave, disenthral every mind and fill the earth with the knowledge of the Lord? Where is the power that is to demolish every pagan temple, grind to dust every idol, abolish all corruptions and take down the great fabric of human society and build it up anew on the principles of holiness? - It is evident that to produce these desirable changes will require the prolonged exertion of some mighty power; where shall we find an agency adequate to such effects?<br><br>In answer to these inquiries, I remark, that in strict language there is but one kind of power in the universe, and that is the power of mind.