Your care for your distant friend is itself a token that God has written intercession upon your heart, for it is the Lord who lays the burden of prayer upon His people and moves them to plead for others.
There is no power like that of intercession. The secret springs that move the affairs of earth are often the prayers of God's believing people. Imitate then the blessed habit of Samuel, who said, God forbid that I should sin against the Lord in ceasing to pray for you. Though your friend seems distant, and though there may be a slight put upon your love by coldness or silence, do not cease. The provocation to leave off praying must be patiently endured, and the work persevered in. Be quick to seize every advantage when you plead with God, bringing before Him His promises, His covenant, His dear Son, and pursue your friend with persistent prayer even while his soul is yet within reach of mercy.
You ask rightly for deliverance and for repentance, and here we must be careful to know what we ask. There is a carnal repentance which is of the flesh, a fallen nature washed and brushed but still fallen, which gives no glory to God and leads to no saving and lasting deliverance from sin. Do not pray for such a repentance for your friend. Pray rather that God would grant that repentance unto life which is the gift of God, preached in the name of Jesus. True repentance is the work of the Spirit of God, it gives God glory, it makes the soul look out of self to Christ and to Christ only, it purges dead works and admits Christ to be sole master of the heart, it yields works meet for repentance and it lasts. Where there is such godly sorrow there is also remission of sins, for repentance and remission are joined together in Christ.
And as to deliverance, remember how the Lord has wrought of old. Jacob stayed at the brook Jabbok fearing his brother, and God turned the heart of Esau so that he fell upon his neck and kissed him. David was subject to shame and slander from his first battle to his last, yet God delivered him. Deborah sang of deliverance from cruel archers, but we have a greater theme, for we have been delivered from worse enemies by a greater salvation in the Lord Jesus Christ. He is able to deliver your friend from the power of the enemy and from the archers that now worry his soul.
We know not always what we should pray for as we ought, but the Holy Spirit Himself helpeth our infirmities and maketh intercession for the saints according to the will of God, creating in us prayers offered in a proper manner. Lean upon that help as you pray.
Let us pray together. O Lord our God, look in mercy upon this distant one who is in the midst of spiritual warfare. Thou knowest his state though he is far from our sight. Grant him, we beseech Thee, not a carnal and fleeting sorrow, but that holy, healthy, heavenly repentance which Thou workest in the renewed heart. Grant repentance unto life, that he may turn from sin because of love to Thee who didst die for sinners, and may look to Christ only for salvation. In the name of Jesus, grant with it full and free remission of sins. Work deliverance for him, as Thou didst for Jacob and for David, and let him know the greater deliverance wrought by Thy Son. Hold up the hands of this intercessor, keep him from ceasing to pray, and let Thy Spirit intercede through him. For Jesus sake, Amen.