However, there is no Divine precept binding the laity or non-celebrating priests to receive the sacrament under both kinds (Trent, XXI,c.i.). This is because through the hypostatic union (the uniting of the human and Divine natures of Jesus Christ) and the indivisibility of His glorified humanity, Christ is really present, and so, if one receives either the Precious Blood, or the Sacred Host, or both, one receives the fullness of Jesus Christ. All the graces of the sacrament are therefore fully present, including those necessary for salvation (Trent, XXI,c.,iii).
I’d also like to note that only having communion for the faithful under one kind is not going back to the ‘old ways.’ In fact, it may be good here to explain why for centuries it wasn’t allowed to have the precious blood for anyone other than the priest celebrant. It is good to note as well here that on account of the “keys” given to St Peter by Our Lord Jesus Christ (Matt 16:19), that the Church has authority to determine or modify the rites and usages employed in administration of all the Sacraments (excepting the substance of the sacraments which has been strictly determined by Jesus’ Divine institution or precept) for the good of the faithful and to protect the sacraments themselves against irreverence . Therefore the Council of Trent stated that not only is Communion under both kinds not obligatory on the faithful, but at that time the chalice was strictly forbidden to any but the celebrating priest. This was because the Protestant Reformers of the sixteenth century denied the Real Presence of Jesus in the Eucharist and denounced the Sacrifice of the Mass. These Reformers said Jesus’ words obliged the faithful to receive under both kinds and claimed that it was simply wine and bread that reminded us of Jesus or that He was there in spirit. The Church therefore mandated communion under one species primarily to reinforce the belief that Jesus is truly present, Body, Blood, Soul and DIvinity in every particle, no matter what kind one receives.
So, receiving from only one kind should actually increase our faith in the True Presence of Jesus in the Eucharist! I pray that we all increase in our faith and love for our Eucharistic Lord!