Vincent's NT Word Studies
42. Continued steadfastly. See on ch. i. 14.Doctrine (didach). Better, teaching.
Fellowship (koinwnia). From koinov, common. A relation between individuals which involves a common interest and a mutual, active participation in that interest and in each other. The word answers to the Latin communio, from communis, common. Hence, sometimes rendered communion, as 1 Cor. x. 16; 9 Corinthians xiii. 14. Fellowship is the most common rendering. Thus Philip. i. 5: "your fellowship in the gospel," signifying co-operation in the widest sense; participation in sympathy, suffering, and labor. Compare 1 John i. 3, 6, 7. Occasionally it is used to express the particular form which the spirit of fellowship assumes; as in Rom. xv. 26; Heb. xiii. 16, where it signifies the giving of alms, but always with an emphasis upon the principle of Christian fellowship which underlies the gift.
Breaking (klasei). Used by Luke only, and only in the phrase breaking of bread. The kindred verb klazw or klaw, to break, occurs often, but, like the noun, only of breaking bread. Hence used to designate the celebration of the Lord's Supper.
Prayers (proseucaiv). Always of prayer to God. Compare on dehseiv, prayers, Luke v. 33; and besought, Luke viii. 38.
Robertson's NT Word Studies
2:42 {They continued steadfastly} (esan proskarturountes). Periphrastic active imperfect of proskarturew as in #Ac 1:14 (same participle in verse #46). {Fellowship} (koinwniai). Old word from koinwnos (partner, sharer in common interest) and this from koinos what is common to all. this partnership involves participation in, as the blood of Christ (#Php 2:1) or co-operation in the work of the gospel (#Php 1:5) or contribution for those in need (#2Co 8:4; 9:13). Hence there is wide diversity of opinion concerning the precise meaning of koinwnia in this verse. It may refer to the distribution of funds in verse #44 or to the oneness of spirit in the community of believers or to the Lord's Supper (as in #1Co 10:16) in the sense of communion or to the fellowship in the common meals or agapae (love-feasts). {The breaking of bread} (tei klasei tou artou). The word klasis is an old word, but used only by Luke in the N.T. (#Lu 24:35; Ac 2:42), though the verb klaw occurs in other parts of the N.T. as in verse #46. The problem here is whether Luke refers to the ordinary meal as in #Lu 24:35 or to the Lord's Supper. The same verb klaw is used of breaking bread at the ordinary meal (#Lu 24:30) or the Lord's Supper (#Lu 22:19). It is generally supposed that the early disciples attached so much significance to the breaking of bread at the ordinary meals, more than our saying grace, that they followed the meal with the Lord's Supper at first, a combination called agapai or love-feasts. "There can be no doubt that the Eucharist at this period was preceded uniformly by a common repast, as was the case when the ordinance was instituted" (Hackett). this led to some abuses as in #1Co 11:20. Hence it is possible that what is referred to here is the Lord's Supper following the ordinary meal. "To simply explain tei klasei tou artou as='The Holy Communion' is to pervert the plain meaning of words, and to mar the picture of family life, which the text places before us as the ideal of the early believers" (Page). But in #Ac 20:7 they seem to have come together especially for the observance of the Lord's Supper. Perhaps there is no way to settle the point conclusively here. {The prayers} (tais proseucais). Services where they prayed as in #1:14, in the temple (#Ac 3:1), in their homes (#4:23).