It is always right to bring these concerns before the Lord, and I can sense your heart’s desire not only for protection but for genuine wisdom and lasting change. You want this young person to finish what was started before rushing into the next thing, and that resonates with the truth that a completed goal brings deep satisfaction. Patience to wait on the right season is a mark of prudence; the simple may plunge ahead, but the one who looks carefully at the path ahead is building on solid ground.
When you ask for mighty justice and protection, remember what Isaiah 54:17 actually means for those who belong to the Lord. He is the covering that shields from heat, the refuge when the storm breaks. No weapon that is formed against His servant can ultimately prosper because He stands as the defender. That kind of safety does not always look like the absence of trouble, but it always means the presence of His care. He knows how to bring justice where there is oppression, and He does not forget the cries of those who trust Him.
The part about cigarettes and alcohol tasting like dog poo is raw, but behind it is a cry for true deliverance from evil habits. The body is a marvel of His design, every breath dependent on the delicate, involuntary work of lungs He made for life and not for poison. When someone turns back to their own ways, they get filled with the bitter harvest of those choices. Yet God can intervene and make what once enticed them become loathsome. The yoke is broken not by willpower alone, but by the anointing that shatters bondage. Pray with confidence that their senses would be revolted by what used to lure them, and that conviction would lead to genuine repentance.
You also want clear boundaries, no smoking around you or the car, and that is not unkind; it is wise. A prudent person guards their own space while still loving the other. You are building rather than tearing down when you refuse to let foolishness take root under your roof.
Since you long for your time together to be blessed and for God to use you for His glory, then keep walking in the fear of the Lord and depart from evil. A life set apart speaks louder than anxious pleas. Those who win souls are those who shine with a quiet, steady light, and the Lord can make even small seeds of witness flourish. Trust Him with the timing of education, military service, and every decision. He declares the end from the beginning; nothing takes Him by surprise. So lay these requests in His hands, rest in His covering, and watch for the fruit He will bring.