If I found out that Socrates had not lived faithfully to his own teaching, would it have an affect on how I viewed his teaching? I don’t think so. True teaching is true teaching and false teaching is false teaching no matter who the teacher is.
Moses was a murderer, yet God used him to deliver the Law to Israel: “Do not commit murder.”
Paul, as a servant of Christ, had a temper, he was outspoken (today we would say too much so), he wrote in frustration that he wished that the teachers of the Law would castrate themselves and he saw conflict as a normal part of life. Yet much of our Christian doctrine is based on Paul’s writing.
David was an adulterer, a murderer and disobeyed the Lord on a number of recorded occasions. Yet, he was a "man after God's own heart" - for all of his faults, David yearned to follow God.
The beauty is in the message, not in the messenger.
May my cry come before you, O LORD;
give me understanding according to your word.
May my supplication come before you;
deliver me according to your promise.
May my lips overflow with praise,
for you teach me your decrees.
May my tongue sing of your word,
for all your commands are righteous.
May your hand be ready to help me,
for I have chosen your precepts.
I long for your salvation,
O LORD, and your law is my delight.
Let me live that I may praise you,
and may your laws sustain me.
I have strayed like a lost sheep.
Seek your servant,
for I have not forgotten your commands.
(note, this is also getting turned in as a "reflection question" for my philosophy class tonight)