1. The Divine Essence and Energies.
God is capable of being known indirectly in the contemplation of the logoi of the creation which manifest him. But God can also be known directly – according to a superior mode passing beyond all cognition but without accessing the essence – by the faithful, who are elevated to the sphere of theologia, by the “realities which are around the essence,”  otherwise called the divine energies.  These correspond to the attributes of God, to the divine properties (inasmuch as they are manifested or are participated), to the divine logoi (considered at their source), to the “invisible realities” of God (cf. Rom. 1.20), to the divine life, or to the glory of God.
These divine energies (which are cognisable, communicable and participable) are relative to, but nonetheless distinct from, the essence (which remains uncognisable, incommunicable and imparticipable). Like the essence, they are uncreated, manifested eternally “around God” like a radiation of this essence. But they are also manifested in the logoi of the creation (without being identified with them), and given as grace to those who are worthy. The divine energies correspond thusly to the “providential procession” according to which God, absolutely imparticipable by essence, is rendered fully participable by his creatures.
Considering the divine energies relative to their manifestation in the creation, Maximus specifies that “every divine energy signifies the whole God indivisibly through this energy in each being, according to that logos through which it is.”  He notes further that “God, who is wholly and commonly in all things and particularly in each being, without division or being divided,” is however none of those beings and is situated beyond all. Hence any pantheist interpretation is excluded and the transcendence of God is preserved.
The distinction of the divine essence and energies has patristic antecedents attested in Athanasius of Alexandria, the Cappadocians (Gregory of Nazianzus, Basil of Caesarea, Gregory of Nyssa), the Pseudo-Dionysius, John Chrysostom and Cyril of Alexandria. But the Confessor gave to this distinction a greater importance than his predecessors, in relation to his theory of the logoi on the one hand, and to his mysticism of divinisation on the other. 
2. The Theory of Logoi.
The cosmology of Maximus is in large part expressed within his theory of logoi.  The notion of logos in general occupies in his thought a fundamental place, and therein receives a development which knows no equivalent in the Greek Fathers.
For Maximus, the logos of a being is its essential reason, that which defines it fundamentally. But it is also its finality, that in view of which it is. In brief, the logos of a being is its raison d’être in the double sense of being the principle and the end of its being. Because this principle and this end are in God, for Maximus, the word logos has primarily a spiritual meaning, and is not reduced to the “natural logos,” as understood by Aristotle.
This then is the principal definition of the notion of logos. But one must know that for Maximus, all the characteristics of beings, both particular and common (whether according to species or genus) come equally from the logoi; that these logoi also govern the relations of beings with each other; and that, in a general manner, they assure the order and cohesion of the universe, both in its movement and in its stability.
The supreme unity of the logoi is realised in and by the Logos, the Word of God himself, who is the principle and the end of all the logoi. The logoi of all beings have in effect been determined together by God in the divine Logos, the Word of God, before the ages, and therefore before these beings were created – it is in him that they are contained before the ages and subsist invariably, and it is by them that all things, before they even came into existence, are known by God. Thus every being, according to its own logos, exists in potential in God before the ages. But it does not exist in act, according to this same logos, except from the time in which God, according to his wisdom, judged it opportune to create that being. Once created according to its logos, it is according to this same logos that God, in his providence, conserves it, actualises its potentialities and directs it toward its end through taking care of it. And in the same way, by his judgment, God assures the maintenance of that being’s difference, which distinguishes it from all other beings.
The logoi of all beings, though being in God and near him, are not God. Not only does Maximus underline the radical transcendence of the Logos in this regard, but he affirms that they were themselves posited by the latter as founded (ὑφεστῶτας) by him. Otherwise said, they are not manifestations of the divine essence. They are no longer divine Ideas in the Platonic sense of the term. Maximus, following Pseudo-Dionysius, calls them divine “volitions (θελήματα)”  – something which signifies above all that they are the inscription of the divine will or intention with regard to each being and that they render manifest this divine design in creation. In thus styling them and in thus linking their origin to the “good will” of God, Maximus links them clearly to the divine economy, which is in fact a work of his will. In this way he clearly distinguishes them from any neoplatonic conception which would make them emanations (or necessary productions) of the divine essence, somehow connatural to God. 
-  Maximus, Amb. 34 (91.1288B); Ep. 6 (91.432C).
-  On the divine energies according to Maximus, see V. Lossky, Théologie mystique (Paris, 1944), 70, 84, 86; ibid., Vision de Dieu, 109–10; P. Sherwood, Earlier Ambigua, 95n.49; ibid., Maximus, 32; ibid., “Maximus and Origenism,” 25–26; A. Riou, Le monde et l’Église, 60–61; L. Thunberg, Man and the Cosmos, 137–40; V. Karayiannis, Maxime le Confesseur, 183–231; J.-C. Larchet, La divinisation, 503–09.
-  Maximus, Amb. 22 (91.1257AB).
-  Maximus, Car. 1.12; 2.27; 4.7; Qu.D. 99 (10.76); 173 (10.120); Amb. 10 (91.1141AB, 1156B); Thal. Prol. (7.41); 13 (7.95–97); 22 (7.141); 39 (7.261); 63 (22.159); Th. oec. 1.48, 50; 2.72, 76.
-  See: I.-H. Dalmais, “La théorie des ‘logoi’”, 244–49; J. Lemaître, “Contemplation chez les Grecs et autres orientaux chrétiens,” Dictionnaire de spiritualité 2.1818–19; P. Sherwood, Earlier Ambigua, 166–80; H. U. von Balthasar, Kosmische Liturgie, 110–17; A. Riou, Le monde et l’Église, 54–63; L. Thunberg, Microcosm and Mediator, 73–79; J.-Cl. Larchet, Divinisation, 112–131.
-  Maximus, Amb. 7 (91.1085A); Thal. 13 (7.95); Pseudo-Dionysius, Div.nom. V.8 (3.824C).
-  Maximus, Amb. 7 (91.1077C, 1080A, 1081AC, 1085A); 10 (1188D–1189B, 1133CD); 15 (1217AB); 17 (1128A–1229A); 21 (1245B); 41 (1309C, 1312B–1313B); 42 (1328AB, 1329BC); Thal. 2 (7.51); 13 (7.51); 55 (7.495); 65 (22.263); Ep. 12 (91.485D).
Source: Jean-Claude Larchet, Saint Maxime le Confesseur, (Paris: Cerf, 2003), 132–36.