I proceeded forth - from God (ἐκ τοῦ Θεοῦ ἐξῆλθον)
Rev., came forth. The phrase occurs only here and in Joh 16:28. Ἑξελθεῖν is found in Joh 13:3; Joh 16:30, and emphasizes the idea of separation; a going from God to whom He was to return (and goeth unto God). Ἑξελθεῖν παρά (Joh 16:27; Joh 17:8), is going from beside, implying personal fellowship with God. Ἑξελθεῖν ἐκ, here, emphasizes the idea of essential, community of being: “I came forth out of.”
And am come (ἥκω)
As much as to say, and here I am.
Of myself (ἀπ' ἐμαυτοῦ)
Of my own self-determination, independently, but my being is divinely derived. See on Joh 7:17.