They were completely convinced.
“To whom also He shewed Himself alive after His passion by many infallible proofs, being seen of them forty days, and speaking of the things pertaining to the kingdom of God.”
– Acts 1:3
The truth is out there. “When He, the Spirit of truth, is come, He will guide you into all truth.” – John 16:13
Just talking a good game? “Which of the two did the will of his father?” – Matthew 21:31
Are we willing to do them? “Do you not know that your body is the temple of the Holy Spirit who is in you, whom you have from God, and you are not your own? For you were bought at a price; therefore glorify God in your body and in your spirit, which are God’s.”…
It could have defined his legacy. “So it was, when the captains of the chariots saw Jehoshaphat, that they said, ‘It is the king of Israel!’ Therefore they surrounded him to attack; but Jehoshaphat cried out, and the Lord helped him, and God diverted them from him.” – 2 Chronicles 18:31 NKJV
It’s one of life’s great uncertainties. “For man also does not know his time: like fish taken in a cruel net, like birds caught in a snare, so the sons of men are snared in an evil time, when it falls suddenly upon them.” – Ecclesiastes 9:12
No one cared when he died. “Thirty and two years old was he when he began to reign, and he reigned in Jerusalem eight years, and departed without being desired. Howbeit they buried him in the city of David, but not in the sepulchres of the kings.” – 2 Chronicles 21:20