In one narration the wording is: "My love is due to those who are sincere to one another for My sake, and My love is due to those who help one another for My sake."
Imam al-Tabarani recorded it in all three of his books, and Imam Ahmad recorded something similar. The narrators of Imam Ahmad are thiqat (trustworthy).
Hadith Referenceمجمع الزوائد ومنبع الفوائد / كتاب الزهد / 18014
Hadith Gradingمحدثین:إسنادہ صحیح
Hadith Takhrij«اخرجه الطبراني فى المعجم الصغير (1095)»