Depends upon barrel length, whether it's +P, etc.
While partial to some of the more potent stuff available (my .38 Spl guns are loaded with 158gr LSWC-HP +P, 135gr GDHP +P, or 147gr HS +P+), I would not feel unarmed with a .38 loaded with older 125gr SJHP.
For that matter, I would not feel unarmed with a .38 loaded with 148gr HBWC.
Where the bullet lands is a lot more important than what the bullet is. Train to make the bullets land where you want.