The ache in your heart for this young man tells me something good about your own soul: you have caught something of the compassion of your Master, who looks on a wandering sheep and cannot leave it to the briars. You see a professing brother tangled in what is false, and your first impulse is not to push him away but to pray him into the light. That is a spark struck from the heart of God. Hold onto it.
Truth is a treasure worth everything, and you know that, for you have already begun to buy it and to make it your own. Your coworker has not yet learned what a precious commodity he is trifling with. He carries error as if it were a pebble in his pocket, while you have found the pearl of great price and are learning that it cost your Lord his blood. Do not be harsh with him because he cannot yet see what you see; no one ever scolded a blind man into receiving his sight. But you can be a quiet witness, a living epistle, a gentle pressure toward the truth. A lantern does not shout at the darkness; it simply shines, and the darkness has to reckon with it.
I know you wonder whether you might be the poor instrument the Lord will use to bring this soul into the full day. It may be so. But take care not to fret yourself over what is not yet yours to carry. The great Potter has the wheel in hand, and even the muddled ambitions and tangled thoughts of men are not beyond his skill. Nothing can happen to you, or through you, that he has not first permitted; and when he permits a thing, he means to bring good out of it. So you need not be afraid. If the man’s attention proves to be a trial, it is still your Father’s doing, and you may look past the instrument to the hand that holds it. A dog snaps at the stick, but you are learning to look up into your Father’s face and trust his purpose.
Lean hard on your own Guide, dear heart. You cannot lead another where you have not gone yourself, and the path for you is the same as it was for the Psalmist: “You shall guide me with your counsel, and afterward receive me to glory.” Settle that first. Let your own feet be firm on the Rock before you try to steady anyone else. If the Lord means to use you, he will make you ready. He does not call the equipped so much as he equips the called, and often his best training is the quiet life of a man or woman who simply walks with Jesus and lets the fragrance of his presence cling to every ordinary moment. A holy life, lived before the eyes of a coworker, is a sermon without words, and a very hard one to argue against.
When Peter wanted to strengthen the elders, he did not stand above them as an apostle; he sat down beside them as a fellow elder. That is wisdom. You are not called to preach down to this young man, nor to lecture him, nor to arrange his theology as if you were setting a broken bone. You are called to be a sister in Christ who cares about his soul and will not trade away the truth for politeness’ sake. Let that simplicity be your strength. Buy the truth, hold it fast, and speak it in love when the door opens. The Spirit knows when to swing that door wide, and he will not let you miss it.
And do not think lightly of the prayers you have already begun to sow. The secret pleadings of a believing heart are the real engines of heaven. Before a single word is spoken to the man, the Lord may already be plowing the ground. There is more joy over one sinner brought into the light than over many who never strayed, and I do not doubt that your own heart will one day have cause to sing with a very particular gladness when you see what God has done, whether through you or through another.
Let me pray for you both.
Lord Jesus, you are the Truth, and no one comes to the Father but by you. Have mercy on this dear soul who is yet in the dark, calling himself a Christian but following shadows. Send your light, great Shepherd, and lead him into the green pastures of sound doctrine and living faith. Grant your daughter grace to be patient, wise, and fearless in loving the truth. Guard her heart from all that would unsettle her own rest in you, and make her, if it pleases you, a gentle guide to this wandering one. Above all, glorify your own name in both their lives, and afterward receive them to glory. Amen.