OBSERVE, comply with, respect, acknowledge, abide by; cling to, adhere to, be faithful to, act up to; meet, fulfill or fulfil; carry out, carry into execution; execute, perform, keep, satisfy, discharge; do ones office.
KEEP FAITH WITH; perform -, fulfill -, discharge -, acquit oneself of- an obligation; make good; make good -, keep- ones -word, - promise; redeem ones pledge; stand to ones engagement.
OBSERVANT, faithful, true, loyal; honorable [See Probity]; true as the dial to the sun, true as the needle to the pole; punctual, punctilious, scrupulous, meticulous; literal (exact) [See Truth]; as good as ones word.
FAITHFULLY &c. adj.; to the letter.
Ignoscito sæpe alteri nunquam tibi.
To God, thy country, and thy friend be true.Vaughan
He that sweareth to his own hurt, and changeth not.Bible