成唯識論述記 6.106

6.106

述曰：若彼救言：定能令心等和合，同趣一境，心起皆有，故是遍者。理亦不然，此觸用故。觸能和合心、心所法，不令離別，同一緣故。

The Commentary states: If they defend their position by saying: 'Concentration can cause the mind and associates to harmonize and together proceed toward one object, and since it is present whenever a citta arises, it is omnipresent'—this principle is also incorrect, because this is the function of contact (sparśa). Contact can harmonize the citta and caitta dharmas, not letting them separate, having them share the same cognitive object.