I know how (oida). Followed by the infinitive oida has this sense. So here twice, with tapeinousqai, to be humbled, from tapeino, and with perisseuein, to overflow. Have I learned the secret (memuhmai). Perfect passive indicative of muew, old and common word from muw, to close (Latin mutus), and so to initiate with secret rites, here only in N.T. The common word musthrion (mystery) is from musth (one initiated) and this from muew, to initiate, to instruct in secrets. Paul draws this metaphor from the initiatory rites of the pagan mystery-religions. To be filled (cortazesqai). Old verb from corto (grass, hay) and so to fatten like an animal. To be hungry (peinain). Old verb from peina (hunger) and kin to penh, poor man who has to work for his living (penomai).