Five times in his pastoral letters Paul passes down a “trustworthy saying” to his pastors-in-training.  Twice he says that these sayings are “deserving of full acceptance.”  He is not saying that the rest of his statements are throwaways — only that these five are distinctively fundamental, foundational, and firm.  They are worth reflecting on.

The saying is trustworthy and deserving of full acceptance, that Christ Jesus came into the world to save sinners, of whom I am the foremost.  — 1 Timothy 1:15

The saying is trustworthy: If anyone aspires to the office of overseer, he desires a noble task.  — 1 Timothy 3:1

For while bodily training is of some value, godliness is of value in every way, as it holds promise for the present life and also for the life to come.  The saying is trustworthy and deserving of full acceptance.  — 1 Timothy 4:9

The saying is trustworthy, for:
If we have died with him, we will also live with him;
if we endure, we will also reign with him;
if we deny him, he also will deny us;
If we are faithless, he remains faithful —
for he cannot deny himself.  — 2 Timothy 2:11-13

But when the goodness and lovingkindness of God our Savior appeared, he saved us, not because of works done by us in righteousness, but according to his own mercy, by the washing of regeneration and renewal of the Holy Spirit, whom he poured out on us richly through Jesus Christ our Savior, so that being justified by his grace we might become heirs according to the hope of eternal life.  The saying is trustworthy.  — Titus 3:4-8a