Garudapurana 1.218.3

1.218.3

oṃ svāgataṃ bhavadbhiriti praśraḥ /
oṃ susvāgatāmiti tairukte oṃ viśvebhyo devebhya etatpādodakamarghyaṃ svāheti devabrāhmaṇapādayordevatīrthenābhugnakuśasahitajaladānam //

The question is: “Oṃ, is it welcome to you?” / When they say, “Oṃ, it is truly welcome,” the offering of water accompanied by unbroken kuśa grass is made at the feet of the divine brāhmaṇa via the deity-tīrtha, reciting: “Oṃ, to the Viśvedevas this foot-washing water and arghya-offering, svāhā!”