The other day I had reason to think about that phrase we often hear, i.e. "only human"… Have you noticed that it's used almost exclusively with failure, usually moral failure? And the word "only" is usually used to diminish the seriousness or importance of whatever, as in "I blew my check at the track, but it's only money". A naughty child says, "but it was only one time."
So the mantra, "I'm or he/she is only human" in the face of lying, extra-marital affairs, stealing, flouting authority, etc. is an attempt to reduce the guilt of such stuff. It's a way of saying, "Hey we all share imperfection, so a guilt shared by everyone really dilutes mine to almost nothing."
On the other hand, my successes are due to talents and virtues that belong to me alone. My self-sacrifice, kindness, honesty, loyalty and bravery are never described as being "only human". My faults I share with whole human race, but my good points are exclusively mine.
Aren't we clever in our sinfulness, self-delusion, self-serving and dishonesty??
The Bible says, "God saw the whole human heart was continually evil." Jesus says, "From the heart proceeds evil thoughts, murders, adulteries, thefts, deceit, pride." That's God's description of our "humanness". It's under His condemnation. We try to use it as an excuse. "Hey I'm only human". That's the problem, isn't it? Who said we didn't need a savior???