  We determine the two loop corrections to the Green's function of a quark
current inserted in a quark 2-point function at the symmetric subtraction
point. The amplitudes for the scalar, vector and tensor currents are presented
in both the MSbar and RI'/SMOM renormalization schemes. The RI'/SMOM scheme two
loop renormalization for the scalar and tensor cases agree with previous work.
The vector current renormalization requires special treatment as it must be
consistent with the Slavnov-Taylor identity which we demonstrate. We also
discuss the possibility of an alternative definition of the RI'/SMOM scheme in
the case of the tensor current.
