of St. Peter with the most stringent oath of fealty to the Pope similar to that which was imposed on
the Italian or suburban bishops.^118
From this time his work assumed a more systematic character in the closest contact with
Rome as the centre of Christendom. Fortified with letters of commendation, he attached himself
for a short time to the court of Charles Martel, who pushed his schemes of conquest towards the
Hessians. Aided by this secular help and the Pope’s spiritual authority, he made rapid progress. By
a master stroke of missionary policy he laid the axe to the root of Teutonic heathenism; with his
own hand, in the presence of a vast assembly, he cut down the sacred and inviolable oak of the
Thunder-God at Geismar (not far from Fritzlar), and built with the planks an oratory or church of
St. Peter. His biographer, Willibald, adds that a sudden storm from heaven came to his aid and split
the oak in four pieces of equal length. This practical sermon was the death and burial of German
mythology. He received from time to time supplies of books, monks and nuns from England. The
whole church of England took a deep interest in his work, as we learn from his correspondence.
He founded monastic colonies near Erfurt, Fritzlar, Ohrdruf, Bischofsheim, and Homburg. The
victory of Charles Martel over the Saracens at Tours (732) checked the westward progress of Islâm
and insured the triumph of Christianity in central Europe.
Boniface was raised to the dignity of archbishop (without a see) and papal legate by the
new Pope Gregory III. (732), and thus enabled to coerce the refractory bishops.
In 738 he made his third and last pilgrimage to Rome with a great retinue of monks and
converts, and received authority to call a synod of bishops in Bavaria and Allemannia. On his return
he founded, in concert with Duke Odilo, four Bavarian bishoprics at Salzburg, Freising, Passau,
and Ratisbon or Regensburg (739). To these he added in central Germany the sees of Würzburg,
Buraburg (near Fritzlar), Erfurt, Eichstädt (742). He held several synods in Mainz and elsewhere
for the organization of the churches and the exercise of discipline. The number of his baptized
converts till 739 is said to have amounted to many thousands.
In 743 he was installed Archbishop of Mainz or Mayence (Moguntum) in the place of bishop
Gervillius (Gewielieb) who was deposed for indulging in sporting propensities and for homicide
in battle. His diocese extended from Cologne to Strasburg and even to Coire. He would have
(^118) The juramentum of Boniface, which he ever afterwards remembered and observed with painful conscientiousness
deserves to be quoted in full, as it contains his whole missionary policy (see Migne, l.c., p. 803):
"In nomine Domini Dei Salvatoris nostri Jesus Christi, imperante domino Leone Magno imperatore, anno 7 post
consulatum ejus, sed et Constantini Magni imperatoris ejus filii anno 4, indictione 6. Promitto ego Bonifacius, Dei gratia
episcopus, tibi, beate Petre, apostolorum princeps vicarioque tuo beato Gregorio papae et successoribus ejus, per Patrem et
Filium, et Spiritum Sanctum, Trinitatem inseparabilem, et hoc sacratissimum corpus tuum, me omnem fidem et puritatem sanctae
fidei catholicae exhibere, et in unitate ejusdem fidei, Deo operante, persistere in quo omnis Christianorum salus esse sine dubio
comprobatur, nullo modo me contra unitatem communis et universalis Ecclesiae, quopiam consentire, sed, ut dixi, fidem et
puritatem meam atque concursum, tibi et utilitatibus tiae Ecclesiae, cui a Domino Deo potestasligandi solvendique data est,
et praedicto vicario tuo atque successoribus ejus, per omnia exhibere. Sed et si cognovero antistites contra instituta antiqua
sanctorum patrum conversari, cum eis nullam habere communionem aut conjunctionem; sed magis, si valuero prohibere,
prohibeam; si minus, hoc fideliter statim Domino meo apostolico renuntiabo. Quod si, quod absit, contra hujus professionis
meae seriem aliquid facere quolibet modo, seu ingenio, vel occasione, tentavero, reus inveniar in aeterno judicio, ultionem
Ananiae et Saphirae incurram, qui vorbis etiam de rebus propriis fraudem facere praesumpsit: hoc autem indiculum sacramenti
ego Bonifacius exiguus episcopus manu propria, ita ut praescriptum, Deo teste et judice, feci sacramentum, quod et conservare
promitto."
With all his devotion to the Roman See, Boniface was manly and independent enough to complain in a letter to Pope
Zacharias of the scandalous heathen practices in Rome which were reported by travellers and filled the German Christians with
prejudice and disobedience to Rome. See the letter in Migne, l.c. p. 746 sqq.