A device for generating opposing fields for shielding an implant in the body of a patient during a magnetic resonance imaging, which device comprises a field generation unit with one or more field generation configured to generate field pulses and a control unit coupled with the field generation unit, and which is configured in such a manner that field pulses can be generated as opposing fields through which, within a spatial zone which contains the implant at least in sections, high-frequency electromagnetic field pulses and/or magnetic gradient field pulses used during the magnetic resonance imaging can be reduced or cancelled out in their intensity through superposition.