What are we to do with Jesus’ interactions with the rich ruler (Luke 18:18-20 and parallels)? Jesus seems to be saying that the way to eternal life is by keeping the law. So too Matt 16:27: when the Son of Man returns he will repay all people for the work they will have done. Further, in the Synoptics we don’t find a John 3:16 or a Pauline statement of justification by faith (cf. Rom 3:22-24; Gal 2:16; Eph 2:8-10). Rather, we find the Sermon on the Mount, with its very demanding standards for ethical behavior. What are we to do with this? Is there an inconsistency between Jesus in the Synoptics and the theology of the rest of the NT?
Several passages in the Synoptics do, in fact, reveal a gospel based on grace, though they do not necessarily use Johannine of Pauline forms/expressions. See these examples (many more could be noted):
• Prodigal Son (Luke 15:11-32, about the grace of the Father toward a rebellious son who comes home in need with empty hands, and who receives blessing beyond all his reasonable expectations—sheer grace).
• Pharisee and Tax Collector (Luke 18:9-14, the one who goes home “justified” [i.e., right with God—not necessarily with connotations of the full Pauline forensic doctrine…] is the humble sinner who prayed and confessed and acknowledged that he had nothing to show but his own sins—there was nothing about himself to be credited, all credit went to the gracious God).
• Luke 7:41-42 (Jesus teaches Simon the Pharisee by means of a story in which two debtors owed a creditor greatly different amounts, and then tells how the creditor cancelled the debts of both so as to highlight the greater love of the one who had had the greater debt; all in all this story seems to allude to the ways of God to cancel the debt of those who don’t deserve it, and there is a leaning toward the idea that it is those who have really large, obvious debts who will have the perception to see their need and seek relief/forgiveness).
• Luke 8:48, 50 (a woman with a flow of blood is made well on the basis of her faith and no merit of any kind; Jairus is told not to fear but only believe and his daughter will be well; these are acts of Christ to bless those who call on him humbly, admitting their need, and seeing that he is willing and able to help them).
• Matt 18:27 (a story about a master who had pity on a servant who could not repay his debts, and so he released the servant and forgave the debts—this is symbolic of the ways of God; yet the story goes on to clarify that the ways of God do not provide this grace in the end to those who respond to it in a manner showing that it has not gripped their hearts and translated into a grace-giving way of life).
• Matt 6:9-13 (the Lord’s Prayer, with Christ's invitation to pray for forgiveness with every expectation that it is available and will be granted simply on the basis of the humble appeal for it; Jesus goes on in Matt 6:25-34 to speak of birds and lilies in such a way as to commend a humble trust, a simple faith resulting in a non-worry lifestyle: a way of life that rests in the Lord for all one needs).
What's more, the Pauline message is replete with commands to be followed (e.g., Rom 12-15; 1 Cor 7-14; Eph 4-6; etc.). Faith alone saves, but faith is something operative--it arouses one to take action (Gal 5:6). The "obedience of faith" Paul calls for (cf. Rom 1:5; 16:26) aligns with the good deeds of the Synoptic Gospels and the good works of James 2:14-26 (faith without works is dead): actions that are rooted in and give practical expression to Christ-centered faith.
