For small input amplitudes both diodes are off and VOUT follows VIN.
When |VOUT| reaches the forward-voltage region, one diode conducts and the output is limited.
At several mA, expect clipping around roughly +/-0.6 to +/-0.75 V rather than an exact +/-0.700 V.
The 1 kOhm series resistor limits diode current to a few mA and is part of the limiter design, not an optional protection component.
