The mind is meant for Jesus, and the mind is made to inflame the heart with passion for Jesus. Henry Scougal explains:
Let us represent [Jesus] unto our minds as we find him described in the gospel; and there we shall behold the perfections of the divine nature, though covered with the veil of human infirmities; and when we have framed unto ourselves the clearest notion that we can of a being, infinite in power, in wisdom, and goodness, the author and fountain of all perfection, let us fix the eyes of our soul upon it (Lamentations 3:58), that our eyes may affect our heart; and, while we are musing, the fire will burn (Psalm 39:3).
Especially, if hereunto we add the consideration of God’s favour and goodwill toward us. Nothing is more powerful to engage our affection to find that we are beloved. Expressions of kindness are always pleasing and acceptable unto us, though the person should be otherwise mean and contemptible: but, to have the love of one who is altogether lovely, to know that the glorious Majesty of heaven hath any regard unto us, how must it astonish and delight us, how must it overcome our spirits, and melt our hearts, and put our whole soul into a flame!” The Life of God in the Soul of Man, 120-121.
Musing upon the gospel is made to set your heart aglow with the gospel. Thinking about God’s love for you, proven in Jesus, is meant to win your heart. Deep thoughts about God’s gospel is not meant to make you smarter but to make your heart burn hotter for Jesus.
This kind of knowledge will not puff up but will create the kind heart that loves because it is deeply beloved.