This post was adapted from a retreat given by Fr. Allan Fitzgerald, OSA on Augustine's Routes to Contemplation.
In Book Seven of the Confessions, he tells us of his first contemplative experience of God after reading the works of the neo-Platonists:
Being admonished by all this to return to myself, I entered into my own depths, with you as guide; and I was able to do it because you were my helper. I entered, and with eye of my soul, such as it was, I saw your unchangeable light shining over that same eye of my soul, over my mind. It was not the light of everyday that the eye of flesh can see, nor some greater light of the same order, such as might be if the brightness of our daily light should be seen shining with a more intense brightness and filling all things with its greatness. Your light was not that, but other, altogether other, than all such lights. Nor was it above my mind as oil is above the water it floats on, nor as the sky is above the earth. It was above because it made me, and I was below because made by it. He who knows the truth knows that light, and he who knows that light knows eternity. Charity knows it (caritas novit eam). O eternal truth and true love and beloved eternity! You are my God. I sigh to you by day and by night.Saint Augustine (Confessions, VII, 10, 16)
For Augustine, lack of charity was equivalent to a kind of blindness or darkness. One who is tied up in self seeking of any kind cannot see beyond himself, let alone set out on the way of contemplation. Love is liberating. It enables us to search for God.
Welcome the unity of mind in the bond of peace, without which no one is able to see God.Saint Augustine (I, 185, 10)
Discord, on the other hand, has the opposite effect:
We are God’s children, and we know it; but we would not know ourselves, if we did not cultivate peace. In creating discord among ourselves, we would no longer enjoy the means of seeing God, we would extinguish our vision. (Sermon 23, 17)Saint Augustine (Sermon 23, 17)
In his treatment of the anima una at the root of contemplation, Athanase Sage refers to religious community and quotes Augustine as he wrote:
For what good is it to know the good, if we don’t love it. But if truth teaches, charity causes one to love in view of a more penetrating knowledge and the enjoyment of such a knowledge.Saint Augustine (Sermon 71, 12, 18)
The anima una is a foretaste of the vision and the beatitude which is promised us and, even in this life, it is able to cause its riches of contemplation to bear fruit, in the measure in which it is exercised whole heartedly In seeing God we know ourselves in the measure of this vision of God. But God in his supreme truth reveals himself only through the progress of fraternal charity.
There is much more that could be gathered to illustrate how Augustine saw love as a route to contemplation. However, that is a task that still lies ahead.
 Sage, Athanase, AA, The Religious Life according to Sanut Augustine, New City Press, New York, 1990, 162-163.