For the Evangelical Calvinist, she believes that God came down, immediately and personally, to humanity because of who he is in himself (antecedently); that is, that God is love (I Jn. 4:8 etc.). The Evangelical Calvinist thinks (at least this one does) that this 'coming down' means that Jesus truly became a human, entered into humanities' sinful state, and began redeeming us (from the inside out) from Christmas time, through his Baptism, into 'Good Friday', climaxing at Easter and Ascension, leading into Pentecost, and finally consummating and being fully realized at his second Advent. This all presupposes that all of sinful humanity was taken care of through the mediatorial and priestly work of Jesus Christ; emphasis is on ALL! In contrast, the classical Calvinist believes that God relates to humanity through abstract, deterministic, impersonal, philosophical decrees. Within the Covenantal/Federal system of Calvinism, this kind of Calvinist believes that God originally related to Adam and Eve through a situation of 'Law-keeping' (Covenant of Works); once Adam and Eve broke God's Law, then the Son and the Father agreed on a contract ('Pactum Salutis' or Covenant of Redemption), which resulted in the Covenant of Grace. This involved the Son coming, meeting the conditions of the Law (that Adam and Eve failed at), paying the legal penalty of death that accrued from original Law Breaking; and in so doing, literally purchasing an elect parcel of humanity for whom the Father and Son had already bartered over in the past (e.g. Unconditional Election). Once Christ fulfills and meets the conditions of the Law (forensically construed), and he purchases this elect group of humanity; then God is able to love this set of humanity.
It should be clear, at this point, why Evangelical Calvinists have a capacity to be incarnational-missional; wherein, the classical Calvinist does not. Since Evangelical Calvinists believe that God 'is' love; then this is what motivates his creating, incarnating, redeeming, and coming for all of humanity. Since classic Calvinists believe that God's primary mode of relation 'is' law; then this results in a theology and practice that sees God only being able to meet the needs of a few elect folk, and not deal with all of humanities' sin problem. Given this scenario, between these two disparate approaches; it should be obvious, by now, that the Evangelical Calvinist can genuinely preach salvation to ALL of creation (Romans 8), instead of just part of it. Myk Habets turned me onto this quote from TF Torrance, years ago now; this quote captures exactly what I have been getting at, in regard to the capacity for the Evangelical Calvinist to be incarnational-missional and evangelistic in a way that is motivated by love for all:
"God loves you so utterly and completely that he has given himself for you in Jesus Christ his beloved Son, and has thereby pledged his very being as God for your salvation. In Jesus Christ God has actualised his unconditional love for you in your human nature in such a once for all way, that he cannot go back upon it without undoing the Incarnation and the Cross and thereby denying himself. Jesus Christ died for you precisely because you are sinful and utterly unworthy of him, and has thereby already made you his own before and apart from your ever believing in him. He has bound you to himself by his love in a way that he will never let you go, for even if you refuse him and damn yourself in hell his love will never cease. Therefore, repent and believe in Jesus Christ as your Lord and Saviour." ~T. F. Torrance, "The Mediation of Christ", 94.PS. Truth be told, I've never liked the language of 'incarnational-missional', because I've always understood the formation and impetus to this kind of language to flow from a theologically Pelagian perspective wherein the emphasis is upon what "I" can perform or do for Christ by way of mimicking my perception of the incarnation. This rubs against a truly Christ-conditioned understanding of Christian practice wherein we live lives that participate in Christ's life for us and others. So just understand that I am not endorsing the usual mode of what it means to be 'incarnational-missional'; which is why I opened up with that word about Billings critique of this movement.