2 Corinthians 4:13

But, we have the same spirit [i.e., type] of faith as that written about [Psa. 116:10], "I believed [God's message], so I spoke." We also believe [it], and so we also speak [about it].

Hebrews 11:1

Now, [having] faith is being sure of [receiving] what is hoped for, and certain [of the existence] of what is not visible.

2 Peter 1:16

For we did not use cleverly conceived stories when we told you about the power and coming of our Lord Jesus Christ, because we were eyewitnesses of His Majesty [i.e., the apostles had personally seen the miraculous power of Jesus].

2 Peter 1:21

For prophecy was never produced by the will of man, but people spoke from God, as they were carried along [i.e., inspired] by the Holy Spirit.

Treasury of Scripture Knowledge

Summary

I believed, therefore have I spoken: I was greatly afflicted:

Therefore

Bible References

I believed

2 Corinthians 4:13
But, we have the same spirit [i.e., type] of faith as that written about [Psa. 116:10], "I believed [God's message], so I spoke." We also believe [it], and so we also speak [about it].
Hebrews 11:1
Now, [having] faith is being sure of [receiving] what is hoped for, and certain [of the existence] of what is not visible.

Therefore

2 Peter 1:16
For we did not use cleverly conceived stories when we told you about the power and coming of our Lord Jesus Christ, because we were eyewitnesses of His Majesty [i.e., the apostles had personally seen the miraculous power of Jesus].