Think nothing and do nothing without a purpose directed to God. For to journey without direction is wasted effort. (St. Mark the Ascetic, The Philokalia, p. 114)
St. Mark’s aphorism has been repeated in many different ways through human history.
If you don’t know your destination, any road will get you there.
A bullet fired from a gun will strike whatever is in its path, whether that is the intended target or not.
St. Mark’s point is that in the Christian life, really for all humans, there is a purpose for our existence, a goal we are trying to attain. We are aiming to attain union with our God who created us. And God, because God is love, lovingly aims to guide us to that goal, a shared life in the Holy Trinity. If we want this to be a conscious effort, it requires us to have a relationship with God
Who is the man that fears the LORD? Him will he instruct in the way that he should choose. (Psalms 25:12)
If we have right relationship with God as Lord, God will guide us to Himself. But that way is not always obvious even to those who have a relationship to God.
Jesus said, “And you know the way where I am going.”
Thomas said to him, “Lord, we do not know where you are going; how can we know the way?”
Jesus said to him, “I am the way, and the truth, and the life; no one comes to the Father, but by me. If you had known me, you would have known my Father also; henceforth you know him and have seen him.”
Philip said to him, “Lord, show us the Father, and we shall be satisfied.”
Jesus said to him, “Have I been with you so long, and yet you do not know me, Philip? He who has seen me has seen the Father; how can you say, ‘Show us the Father’? (John 14:4-9)
Apparently it is even possible to walk with Christ and not understand the way or the destination! We have to see our relationship to Christ as the Way to union with God. When we see our life as directed to God, then we will understand the walk with Christ. We will know both the Way and the destination.