Not only did he forfeit his soul and condemned himself to eternal death, but Gpdpinished him on earthfor the rest of his days. His firstborn child with Bathsheba was stillborn, his daughter was raped and was never right again, and Absalom, his favorite, was also killed by David’s own soldiers. He was never permitted to build the Temple and Solomon ended up a lecher who caused the downfall of Israel.
I can think of several important scriptures that militate against your conclusions.
Hebrews 11
32 And what more shall I say? For the time would fail me to tell of Gideon and Barak and Samson and Jephthah, also of David and Samuel and the prophets: 33 who through faith subdued kingdoms, worked righteousness, obtained promises, stopped the mouths of lions, 34 quenched the violence of fire, escaped the edge of the sword, out of weakness were made strong, became valiant in battle, turned to flight the armies of the aliens. 35 Women received their dead raised to life again.
Others were tortured, not accepting deliverance, that they might obtain a better resurrection. 36 Still others had trial of mockings and scourgings, yes, and of chains and imprisonment. 37 They were stoned, they were sawn in two, were tempted,[f] were slain with the sword. They wandered about in sheepskins and goatskins, being destitute, afflicted, tormented— 38 of whom the world was not worthy. They wandered in deserts and mountains, in dens and caves of the earth.
39 And all these, having obtained a good testimony through faith, did not receive the promise, 40 God having provided something better for us, that they should not be made perfect apart from us.
Matthew 1
1 The book of the genealogy of Jesus Christ, the Son of David...