The degree of moral assurance of salvation we can attain to is very high. The point is to examine ourselves to see if we are mired in serious sin, and to repent of it. If we do that, and know that ...

"the hope of salvation" [1 Thess 5:8] or "hope of eternal life" [Titus 1:2; 3:7]. If we were assured of heaven, then there would be no need for hope. Hope is not the same as assurance (Romans 8:24).